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ICM soft failure by Yellow-88
Started on: 07-23-2024 02:55 PM
Replies: 40 (536 views)
Last post by: Dukesterpro on 08-05-2024 01:50 PM
Yellow-88
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Report this Post07-23-2024 02:55 PM Click Here to See the Profile for Yellow-88Send a Private Message to Yellow-88Edit/Delete MessageReply w/QuoteDirect Link to This Post
Hi

It's always been my experience that an ignition control module will just plain fail. Sudden no spark, no fuel. But ... it looks like they can just "act up".

Because the tachometer sees ONLY primary ignition, an unsteady tach is the first symptom of a primary ignition issue. As it gets worse, hesitation, sag and stumble along with bouncy tach needle sets in. If letting it cool off temporarily fixes the problem, it's a half cooked ICM.

The ICM cools it self by heat sinking into the distributer base that lives in a hot environment. Not a great design.
Any ideas on how to help keep it cool? I'm considering better heat shielding design for one.
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Report this Post07-23-2024 03:38 PM Click Here to See the Profile for PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Yellow-88:

Any ideas on how to help keep it cool?


Installed heatsink on distributor under ignition module

 
quote
Originally posted by Yellow-88:

I'm considering better heat shielding design for one.


In addition to the heat sink I installed 16 years ago (and that ACDelco ICM is still working just fine), I also installed a much larger heat shield extension protecting the distributor from the heat of the EGR valve and tube. The white arrows indicate the two ends of the shield. It extends right down to the intake manifold. This required that the coolant tubes to the TB also be removed, but the side benefit of this is that there's now less heat in the immediate area around the distributor, as the coolant tubes themselves get plenty hot.

[This message has been edited by Patrick (edited 07-23-2024).]

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Report this Post07-23-2024 06:33 PM Click Here to See the Profile for theogreClick Here to visit theogre's HomePageSend a Private Message to theogreEdit/Delete MessageReply w/QuoteDirect Link to This Post
When you have "Bad ICM" often isn't just "Bad ICM" but other things killing it.

Heat Sink can help or not depending what else is killing it.

Pull tach filter because that can cause ignition problems then kill the ICM.
See https://web.archive.org/web...t/~fierocave/hei.htm

------------------
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Report this Post07-23-2024 07:21 PM Click Here to See the Profile for cartercarbaficionadoSend a Private Message to cartercarbaficionadoEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Yellow-88:

Hi

It's always been my experience that an ignition control module will just plain fail. Sudden no spark, no fuel. But ... it looks like they can just "act up".

Because the tachometer sees ONLY primary ignition, an unsteady tach is the first symptom of a primary ignition issue. As it gets worse, hesitation, sag and stumble along with bouncy tach needle sets in. If letting it cool off temporarily fixes the problem, it's a half cooked ICM.

The ICM cools it self by heat sinking into the distributer base that lives in a hot environment. Not a great design.
Any ideas on how to help keep it cool? I'm considering better heat shielding design for one.

oh yeah dealt with killing 14 of them a year ago since the only one that worked had a wandering idle. long story short a dying or out of whack pickup will kill these very fast
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Report this Post07-23-2024 07:25 PM Click Here to See the Profile for Yellow-88Send a Private Message to Yellow-88Edit/Delete MessageReply w/QuoteDirect Link to This Post
Hi

I said that the tack sees only the primary ignition ... ( and I'll add) ... and that includes the tack filter. Anything happening in the primary ignition with affect the tack. It's just that the tack is very sensitive and will show tiny PI issues before you feel them.

I like the fined heat sink addition. They are readily available sized to fit our distributor. Like the module, they need thermal paste.
But they're still in a nasty hot place. So a better heat shield is a logical addition. Heat shields keep the JWT from frying so it makes sense to me.

I think I found a better ICM. Is anyone familiar with this one?

https://www.summitracing.com/parts/acc-35370

https://www.summitracing.co...Y-Pp9vxoCr3gQAvD_BwE
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Report this Post07-23-2024 07:33 PM Click Here to See the Profile for cartercarbaficionadoSend a Private Message to cartercarbaficionadoEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Yellow-88:

Hi

I said that the tack sees only the primary ignition ... ( and I'll add) ... and that includes the tack filter. Anything happening in the primary ignition with affect the tack. It's just that the tack is very sensitive and will show tiny PI issues before you feel them.

I like the fined heat sink addition. They are readily available sized to fit our distributor. Like the module, they need thermal paste.
But they're still in a nasty hot place. So a better heat shield is a logical addition. Heat shields keep the JWT from frying so it makes sense to me.

I think I found a better ICM. Is anyone familiar with this one?

https://www.summitracing.com/parts/acc-35370

https://www.summitracing.co...Y-Pp9vxoCr3gQAvD_BwE

yeah a fiero owner a few towns over is running one. he says like the rest it's a hit or miss on how it runs between modules. sometimes you get a bat out of hell and other times it's just slow. he does have a killer custom intake and performance mods so I'm inclined to believe him
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Yellow-88
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Report this Post07-23-2024 07:36 PM Click Here to See the Profile for Yellow-88Send a Private Message to Yellow-88Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by cartercarbaficionado:

oh yeah dealt with killing 14 of them a year ago since the only one that worked had a wandering idle. long story short a dying or out of whack pickup will kill these very fast


Hey Carter

That's 14 hundred dollars in ICMs. Yicks ..... or where they the "economy" ones?

Is that true? Can a pick up coil issue kill an ICM? What else can?
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Report this Post07-23-2024 07:39 PM Click Here to See the Profile for cartercarbaficionadoSend a Private Message to cartercarbaficionadoEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Yellow-88:


Hey Carter

That's 14 hundred dollars in ICMs. Yicks ..... or where they the "economy" ones?

Is that true? Can a pick up coil issue kill an ICM? What else can?

I tried a mixture of economy and oem ones and a performance one and believe it or not the best one was the cheapest one autozone had. had the most power and best fuel economy and screamed to 6k quite fast but didn't last long.
for longevity apparently the best ones are Delphi but that was the one that ran like crap. but it did run the longest out of any so there's that.
yeah the modules are pretty fragile and a whacky pickup like mine which was pretty much always telling it to fire slightly (not fully just enough to make it try over and over) will kill it in short order
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Report this Post07-23-2024 07:46 PM Click Here to See the Profile for PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Yellow-88:

I think I found a better ICM. Is anyone familiar with this one?


Better than what? Better than a genuine ACDelco unit?


 
quote
Originally posted by Yellow-88:

ACDelco GM Genuine Parts Ignition Module Heat Sinks


It's rather small. The finned area is very limited.


In regards to the pickup coils... they're inexpensive, and it should be standard practice to replace them when the ICM is replaced.

[This message has been edited by Patrick (edited 07-23-2024).]

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Yellow-88
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Report this Post07-23-2024 08:15 PM Click Here to See the Profile for Yellow-88Send a Private Message to Yellow-88Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Patrick:

It's rather small. The finned area is very limited.


In regards to the pickup coils... they're inexpensive, and it should be standard practice to replace them when the ICM is replaced.



Better meaning that it "may" be built to a higher standard than OEM because it's intended for competition use. Accel offers one for OEM replacement also at the same price as ACDelco. There are also ICMs listed for marine use by suppliers who sell to that industry. Are there different standards?

Yes I know about pickup coils. Green patina means the copper is exposed, because the insulation coating has fried. It's a good chance to clean the distributor body also.

Yes the store bought heat sink is small but bigger than the bottom of the distributer alone.
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Report this Post07-23-2024 10:38 PM Click Here to See the Profile for pmbrunelleSend a Private Message to pmbrunelleEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Yellow-88:
Better meaning that it "may" be built to a higher standard than OEM because it's intended for competition use. Accel offers one for OEM replacement also at the same price as ACDelco. There are also ICMs listed for marine use by suppliers who sell to that industry. Are there different standards?


Open up an Accel module, and we may be able to make some evaluations about its build quality.

Here are some modules I opened:

GM stock Fiero:


Wells/WVE:



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Report this Post07-23-2024 10:48 PM Click Here to See the Profile for pmbrunelleSend a Private Message to pmbrunelleEdit/Delete MessageReply w/QuoteDirect Link to This Post

pmbrunelle

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The Accel ICM appears to be the 18.58$ (Canadian dollars) WAI GLOBAL DM1990XHD with an Accel sticker on it.


Visually, the Accel appears to be an exact match with it. For instance, look at the metallic-colored flat area around the left screw hole. Look at the brass tube with teeth on the right screw hole. Exactly the same as the WAI GLOBAL.
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Report this Post07-24-2024 01:52 AM Click Here to See the Profile for PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by pmbrunelle:

Visually, the Accel appears to be an exact match with it. For instance, look at the metallic-colored flat area around the left screw hole. Look at the brass tube with teeth on the right screw hole. Exactly the same as the WAI GLOBAL.


You're right... externally, these ICMs are identical. It's difficult to believe that Accel would take an el cheapo ICM that RockAuto sells for $13.50, put a sticker on it, and then jack the price up to $158.95 for some sucker to come along. The guts have got to be different... but damn, look at them!



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Report this Post07-24-2024 03:41 AM Click Here to See the Profile for cyrus88Send a Private Message to cyrus88Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Patrick:

You're right... externally, these ICMs are identical. It's difficult to believe that Accel would . . .


Lol! It's not difficult to imagine at all. There's a lot of ratF@#%kery that goes on in every industry and automotive is no exception. If you ever watch Samcrac on youtube you'll see that he buys some replacement parts for his Lambo from the VW dealer because the Lambo dealer jacks up the price for the exact same part.

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Report this Post07-24-2024 01:57 PM Click Here to See the Profile for Yellow-88Send a Private Message to Yellow-88Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Patrick:

You're right... externally, these ICMs are identical. It's difficult to believe that Accel would take an el cheapo ICM that RockAuto sells for $13.50, put a sticker on it, and then jack the price up to $158.95 for some sucker to come along. The guts have got to be different... but damn, look at them!





Yes, they do look identical. I just bought a Delphi #10059 and it also looks identical to these two. The brand and part number is laser etched into it. Not blank or a sticker. This is the one our local Chevy dealer uses and is priced at $153. It sells every where for $60 -$100. Others pictured on this forum and elseware do look different. There appears to be 2 different case styles and different guts. The obvious difference being at the bolt locations. My old one with a GM logo embossed into it is the style different than what's pictured here. (both bolt holes have the same pressed in grommets.) My part number research reveals that there are a LOT of part numbers that cross reference between GM models and still bare the "genuine GM part" claim.

This kind of component is made up from parts supplied by companies that often make parts for unrelated industries. Often it's the procurement guy who make the choice about what to buy. He may be a new guy trying to look good. "Wow, just got a great deal on transistors". And, who actually assembles these things ....... ??

We do need to realize that these are "old car" parts, and there are no more Pontiac dealers. Yes, retail can get brutal. Yes, repackaged old stock bought at a closeout can happen. Personally, if I bought a boat load of high quality old stock parts wicked cheap, I'd sell them at a lower price but not so low as to turn people off.

As it turns out here are a few issues that can kill a ICM but heat comes out at the top of the list. I'm going to put some effort into making a really nice heat shield.
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Report this Post07-24-2024 02:10 PM Click Here to See the Profile for Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post
We've had very bad experiences with Accel products That includes the so called "Performance coils" that do not last long. There seems to be a lot of rebranded cheap chicom product on the automotive replacement market these days. It's getting difficult to tell good parts from bad parts until you use them.
We have a test jig for ignition modules here so we can always determine if the ignition module is good or bad. Autozone also has a tester for these but it seems the personnel in the store doesn't know how or even if they have a test jig. You see a sign in the window that says we can test all kinds of products and you go in the store and they say "what"?

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
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Report this Post07-25-2024 02:35 AM Click Here to See the Profile for cartercarbaficionadoSend a Private Message to cartercarbaficionadoEdit/Delete MessageReply w/QuoteDirect Link to This Post
[QUOTE]Originally posted by Yellow-88:


Yes, they do look identical. I just bought a Delphi #10059 and it also looks identical to these two. The brand and part number is laser etched into it. Not blank or a sticker. This is the one our local Chevy dealer uses and is priced at $153. It sells every where for $60 -$100. /QUOTE]
that explains why my Delphi unit never ran very well. I'm not even sulrised that there's 14 rebrands. just found out it the 300 dollar coil packs my friend bought for that 95 gtp I've mentioned before are accel. and under that sticker is a random bunch of Chinese characters so that explains why they lasted 8 months before exploding
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Report this Post07-25-2024 04:53 PM Click Here to See the Profile for Yellow-88Send a Private Message to Yellow-88Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by cartercarbaficionado:

I tried a mixture of economy and oem ones and a performance one and believe it or not the best one was the cheapest one autozone had. had the most power and best fuel economy and screamed to 6k quite fast but didn't last long.
for longevity apparently the best ones are Delphi but that was the one that ran like crap. but it did run the longest out of any so there's that.
yeah the modules are pretty fragile and a whacky pickup like mine which was pretty much always telling it to fire slightly (not fully just enough to make it try over and over) will kill it in short order


So ... you see a difference in how the engine runs with different ICMs? Has anybody else seen that?
You've tested them long enough to see a change in fuel economy?
The cheap Autozone one was the best but didn't last? How many miles did it go?
So ... all of the ones you tested where with a bad pickup coil? " .... telling it to fire slightly (not fully just enough to make it try over and over)" ???

My new Delphi defiantly doesn't run like crap and if it goes another 50 K miles like the last original GM one did, I'll be happy.

I think a better heat shield is the key to TPS longevity. That's on my list.

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Report this Post07-25-2024 04:57 PM Click Here to See the Profile for Yellow-88Send a Private Message to Yellow-88Edit/Delete MessageReply w/QuoteDirect Link to This Post

Yellow-88

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Sorry ... I meant ICM not TPS.
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Report this Post07-25-2024 05:18 PM Click Here to See the Profile for Yellow-88Send a Private Message to Yellow-88Edit/Delete MessageReply w/QuoteDirect Link to This Post

Yellow-88

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Hi

I think it's time to defend Chinese electronics. Your cell phone is Chinese. So is most of your computer. They are good at making electronic stuff. Every Country is capable of making poor quality stuff and China is no exception. We actually have no idea where these parts come from. Nobody will get sued over defective old car parts. Corporate ethics is no longer a thing. There is no oversight watchdog paying attention. In my day even the parts counter guy felt responsible for poor quality parts because his reputation was at stake. Welcome to the new world.
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Report this Post07-28-2024 10:18 PM Click Here to See the Profile for OH10fieroSend a Private Message to OH10fieroEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Yellow-88:

Hi

I think it's time to defend Chinese electronics. Your cell phone is Chinese. So is most of your computer. They are good at making electronic stuff. Every Country is capable of making poor quality stuff and China is no exception. We actually have no idea where these parts come from. Nobody will get sued over defective old car parts. Corporate ethics is no longer a thing. There is no oversight watchdog paying attention. In my day even the parts counter guy felt responsible for poor quality parts because his reputation was at stake. Welcome to the new world.


The main factor is cost. When sending bids out corporations will constantly send them back for rebid or flat out tell manufactures what they want the cost per unit to be, when this happens quality is the thing to be sacrificed. Also, when going with manufacturing in countries outside the US the regulations that affect the quality of parts have a series of loopholes that allow corporations to ignore in order to maximize profits.
If products from outside US manufacturing was subjected to the exact same regulations as the US this conversation would be a rare occurrence instead of popping up every couple months.
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Report this Post07-29-2024 07:44 AM Click Here to See the Profile for 82-T/A [At Work]Send a Private Message to 82-T/A [At Work]Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Yellow-88:
Hi

I think it's time to defend Chinese electronics. Your cell phone is Chinese. So is most of your computer. They are good at making electronic stuff. Every Country is capable of making poor quality stuff and China is no exception. We actually have no idea where these parts come from. Nobody will get sued over defective old car parts. Corporate ethics is no longer a thing. There is no oversight watchdog paying attention. In my day even the parts counter guy felt responsible for poor quality parts because his reputation was at stake. Welcome to the new world.



I would disagree...

You can still make things in China with literally no quality control or standards. I'm at least old enough to remember when we thought the same thing about Japanese products... and most of their stuff was crap at the time, but it eventually did get better by the mid 80s, and exceeded reliability of American products. Now Japan makes some of the most precise measuring instruments in the world. China has not reached that level yet overall, but it has in some areas, specifically things like mechanical watches, cell phones, and computer equipment. That's because the QA/QC is managed by an American company (e.g., Apple, Samsung, etc.). But the run of the mill reproduction parts from China are still basically garbage. You only use those parts if you are desperate. Another example with China. I rebuild Swiss watches as a weird hobby. China (Seagull) bought the ValjouX 7750 movement manufacturing components, and now reproduce them in China (along with other movements, like the ETA 2840). The design is essentially the same ... mechanically, but the difference between them and the Swiss is the quality control. The Swiss build watches in lab coats, hair nets, and sterile gloves. The Chinese do it in factories... so you get skin flakes, dust, hair, and other things in the watch movements that can prevent them from running right. Now, look at ignition control modules... it would be the same as perhaps not properly applying sealant everywhere it should... this is quality control... which China simply does not have for most things produced there.

As for corporate ethics... it's the opposite of what you say. Corporate compliance and ethics were never a thing in the 50s - 2000s. It's a burgeoning "industry" if you will, and companies now have Code of Conduct, Privacy Standards, and a dozen other compliance and ethics programs that are either mandatory by regulations, or encouraged as a result of competition (ESG, whatever). There is/are more corporate ethics today than at any time in world history.
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Report this Post07-29-2024 11:04 AM Click Here to See the Profile for Yellow-88Send a Private Message to Yellow-88Edit/Delete MessageReply w/QuoteDirect Link to This Post
Hi

OK, corporate ethics has improved but the desire to be seen as "reputable" has not changed.
Quality control has always been expensive so it's a "logical" cost savings area. Both the aerospace industries and "high visibility" consumer products get the most attention from QC departments, bean counters and marketing people. Naturally, aerospace stuff gets the highest level of QC. Dangling details left to the bottom corners of manufacturing like old car replacement parts don't need to worry. I think that applies to all countries. You'll never see a ICM quality problem on the news.

I asked in a separate thread about defective new parts because there seems to be a lot of talk about it but I personably have not seen one.
This thread was supposed to be about how and why ICMs fail.

I've always been intrigued by precision mechanical devices. Sounds like a fun hobby.
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Report this Post07-29-2024 12:17 PM Click Here to See the Profile for Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post
To add to the discussion there is a difference in manufacturing a complete product (that usually has a warranty) than making replacement parts. The replacement market business usually goes to the lowest bidder while the completed product has to strive for consumer acceptance. . Its a difference of just throwing something in a box to marketing a product where you are selling features, quality and reliability. Its the short term vs the long term With Chicom replacement auto parts; its a roll of the dice. The monthly pallets of returned parts at my local Autozone tell the story. Also look online at the many horror stories of Chicom tires blowing up. I recently spoke to a guy that has had a distributor rotor melt.
The market is now saturated with Chicom fuel pumps, alternators, water pumps , wiper blades and electrical parts.
If you find good replacement parts that last buy them now. Our cars are getting old and its only time before they become obsolete.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

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Report this Post07-29-2024 12:40 PM Click Here to See the Profile for Yellow-88Send a Private Message to Yellow-88Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Dennis LaGrua:

To add to the discussion there is a difference in manufacturing a complete product (that usually has a warranty) than making replacement parts. The replacement market business usually goes to the lowest bidder while the completed product has to strive for consumer acceptance. . Its a difference of just throwing something in a box to marketing a product where you are selling features, quality and reliability. Its the short term vs the long term With Chicom replacement auto parts; its a roll of the dice. The monthly pallets of returned parts at my local Autozone tell the story. Also look online at the many horror stories of Chicom tires blowing up. I recently spoke to a guy that has had a distributor rotor melt.
The market is now saturated with Chicom fuel pumps, alternators, water pumps , wiper blades and electrical parts.
If you find good replacement parts that last buy them now. Our cars are getting old and its only time before they become obsolete.



Yes, that's what I mean by, "Dangling details left to the bottom corners of manufacturing like old car replacement parts don't need to worry."

"The monthly pallets of returned parts at my local Autozone tell the story." Really? Pallets? Monthly? And Autozone is still in business?
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82-T/A [At Work]
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Report this Post07-29-2024 12:57 PM Click Here to See the Profile for 82-T/A [At Work]Send a Private Message to 82-T/A [At Work]Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Yellow-88:
I asked in a separate thread about defective new parts because there seems to be a lot of talk about it but I personably have not seen one.
This thread was supposed to be about how and why ICMs fail.


I've not seen that thread, but I will say that I've run into several shoddy parts... but less frequently I'd say.

Back in the late 90s, when my Fiero was my only car, and I didn't have a lot of money... I'd have to routinely replace things like alternators, ignition control modules, O2 sensors... what have you.

It's possible that they failed for some other reason that led to the original failing, but in most cases... it was just poor quality control. Alternators for example, were a big problem that I ran into. They'd usually only last a year or so. I think I went through 3 alternators in my 87 Fiero from 1996-1999, and the original one lasted almost a decade. Things like waterpumps... I bought a "Holley" water pump for my V6 from Coltec Industries. I was told it was high performance because it had a plastic impellar which made it spin faster or less drag or some nonsense. I believed this since I was young and dumb, until such point the impeller broke free from the pulley and my engine overheated.

And with ignition control modules... I actually bought one of those Accel ICMs. I don't remember if it failed. I did have an Accel ignition coil, and Accel injectors on my Fiero as well (17# injectors). While I didn't have any of the problems that others are saying they had, I will say that I went through several ignition control modules and MAP sensors before I went back to AC DELCO / GM, and never had a problem. My car even has the engine fan which directs cool air towards the ignition coil.

Just one of those things...


If I had to throw out a wild guess, I'd stick to mostly OEM makes... AC DELCO, or DELPHI... since they seem to have better quality control (in my experience).


EDIT to say... most of the shoddy parts I purchased from places like Discount Auto Parts, or Advanced Auto Parts "back in the day." Most of these (for example, alternators) were simply rebuilt used parts. Like... they didn't even re-work everything. They'd take junkyard alternators, disassemble them, replace the bearings and a few other things... hot tank the case, install a new pulley and connector, and slap it all back together and put a sticker on it. That was "bronze" level... GOLD was where you actually got all new parts.

[This message has been edited by 82-T/A [At Work] (edited 07-29-2024).]

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armos
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Report this Post08-04-2024 06:25 PM Click Here to See the Profile for armosSend a Private Message to armosEdit/Delete MessageReply w/QuoteDirect Link to This Post
It might be interesting if we could collect internal photographs of different ICMs - then we'd really know which ones are the same and which are different, and depending on the detail might even be able to tell which are using better components. But I don't think they can be opened easily.
If people start doing that though, it would make sense to collect those photos in a new thread with a title dedicated to that purpose.


I've never had a V6 ICM die, but I guess I'm lucky about that. When I got my 86 in 2010, it came with 2 aftermarket ICMs - one installed and one loose in the trunk. IIRC I swapped to the other ICM out of curiosity and they both worked. The previous owner must have been swapping them, but I don't think they had any fault.
Later I got a couple GM modules from eBay at a good price, and I've had one of those installed ever since. The old aftermarket ones were still working though.

When I got my car it did have an intermittent ignition issue, so I think that's why the PO was messing with the ICMs, but that was caused by a broken connector. I also had a fusible link burn out on me in a few months, so he could have had early symptoms from that I suppose. At some point I replaced the pickup coil and the ignition coil, but I don't remember if I had a good reason. None of my ICMs ever turned up dead though.

It's logical that cooling them will only help them, but I'm not sure how often that's the real cause of death. Have people with chronic ICM issues found that they were solved when they added cooling?

Although I haven't done anything specifically to cool my ICM, it might not run as hot as in some cars. I do have the cooling tubes that blow air into that area (really it blows on the ignition coil). The engine bay might also not get quite as hot since I don't use the stock radiator fan switch. Most of my driving trips also aren't very long. I did drive cross-country a few years ago, but that's at interstate speeds, not idling in traffic.
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Report this Post08-04-2024 06:41 PM Click Here to See the Profile for PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by armos:

Have people with chronic ICM issues found that they were solved when they added cooling?


My ICM failure (as mentioned Here) wasn't "chronic" as it only ever happened once... but the ICM failure was directly related to my plugged cat at the time which caused the engine bay temperatures to skyrocket.
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Report this Post08-04-2024 07:05 PM Click Here to See the Profile for 82-T/A [At Work]Send a Private Message to 82-T/A [At Work]Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Patrick:

My ICM failure (as mentioned Here) wasn't "chronic" as it only ever happened once... but the ICM failure was directly related to my plugged cat at the time which caused the engine bay temperatures to skyrocket.



Speaking of... I was cleaning up my daughter's stock exhaust system (really good shape, and original... so I just lightly sanded it and painted it with 2000 degree ceramic paint, which I'm sure will all completely flake off the first time we start the car)... but never the less... the original catalytic converter was on the car. It was one of those charcoal pellet-style cats. I replaced it with one of the Ocelot ones from the Fiero Store (which fit perfect), but when I started shaking the muffler... it was completely filled with little charcoal balls. It took me forever of shaking it around and turning the whole thing around in order to get all the little pellets to eventually work their way out of the muffler.

Ugh...
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Report this Post08-04-2024 07:15 PM Click Here to See the Profile for PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by 82-T/A [At Work]:

...the original catalytic converter was on the car.


My Formula (different Fiero than the one with the plugged cat) still has it's original pellet style cat. Whether the pellets are still in the cat or not, I don't know... but that engine has always run well, and I don't notice any strong odors from the exhaust.
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Report this Post08-04-2024 07:47 PM Click Here to See the Profile for 82-T/A [At Work]Send a Private Message to 82-T/A [At Work]Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Patrick:

My Formula (different Fiero than the one with the plugged cat) still has it's original pellet style cat. Whether the pellets are still in the cat or not, I don't know... but that engine has always run well, and I don't notice any strong odors from the exhaust.



Do you still have to get it emissions inspected? My assumption is that it started to rust a little inside, which allowed the pellets to go with the exhaust into the muffler. The only issue I perceive is that these pellets would retain heat (though how much heat there would be in the muffler, who knows) and that could make that whole area hotter, longer...

Either way... the replacement honeycomb catalytic converters are a little bit more efficient. They generally flow better, and also heat much more quickly allowing them to do their job faster as well. But it was a decent design. I weighed mine... it was 13 pounds... compared to the Ocelot one which is about 4 pounds.
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Report this Post08-04-2024 08:17 PM Click Here to See the Profile for PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by 82-T/A [At Work]:

Do you still have to get it emissions inspected?


No... so except for a lack of smell (which is good), I have no definitive proof that the cat is actually still doing its job. I had bought an aftermarket cat for my Formula about a dozen years ago, but I put off installing it until it was obvious that the original cat had failed. I'm still waiting!

 
quote
Originally posted by 82-T/A [At Work]:

Either way... the replacement honeycomb catalytic converters are a little bit more efficient. They generally flow better, and also heat much more quickly allowing them to do their job faster as well.


Interestingly enough, it was the newer style cat that failed (and then plugged up) on my '86 GT.

CLICK FOR FULL SIZE
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Report this Post08-05-2024 12:05 AM Click Here to See the Profile for armosSend a Private Message to armosEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Patrick:

Interestingly enough, it was the newer style cat that failed (and then plugged up) on my '86 GT.

CLICK FOR FULL SIZE


That's the same mess I found on my 86GT, except it didn't stay in the cat. My muffler was rattling, then it split open. When I took the exhaust apart to replace the muffler I found those little honeycomb bits all through everything, and half the pathway through the cat had converted to free flow.

The old cat was aftermarket, my notes say the date code was from Dec 2000, so it was <10 years old when I got the car in 2010 (already broken up and rattling).
But to be fair - before I found the problem with my ignition, the car did an impressive "Uncle Buck" style backfire on me once. Who knows how many times it happened before. I'm sure that didn't help the cat stay in one piece.

The current aftermarket cat is 12 years old now and no rattling yet, so I guess that's good. I do think it's degraded though, based on my last test before I moved.
Factory cats are probably more durable, if it's lived a happy life maybe it's possible for one of those to still work.

[This message has been edited by armos (edited 08-05-2024).]

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Report this Post08-05-2024 12:19 AM Click Here to See the Profile for PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by armos:

That's the same mess I found on my 86GT, except it didn't stay in the cat. My muffler was rattling, then it split open. When I took the exhaust apart to replace the muffler I found those little honeycomb bits all through everything, and half the pathway through the cat had converted to free flow.


I was fortunate. The outlet end (shown below) of my broken up cat was still intact, which prevented the innards from travelling downstream into my muffler... although when the engine was revved, I could see white "dust" coming out of my exhaust tips.

CLICK FOR FULL SIZE
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Report this Post08-05-2024 07:48 AM Click Here to See the Profile for 82-T/A [At Work]Send a Private Message to 82-T/A [At Work]Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Patrick:

Interestingly enough, it was the newer style cat that failed (and then plugged up) on my '86 GT.




Yeah... those factory cats were built to last... just an inferior design I think (in terms of flow)... but well engineered. I hit a coconut on the highway, and it dented my catalytic converter, which actually saved it from hitting my oil pan. But it was like only a couple of weeks after that everything was rattling... just like this.
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Report this Post08-05-2024 09:19 AM Click Here to See the Profile for Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post
For everyone's sake I will start a new thread where we can list all the imported parts that have worked and lasted.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

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Report this Post08-05-2024 12:41 PM Click Here to See the Profile for DukesterproSend a Private Message to DukesterproEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by 82-T/A [At Work]:
Yeah... those factory cats were built to last... just an inferior design I think (in terms of flow)... but well engineered. I hit a coconut on the highway, and it dented my catalytic converter, which actually saved it from hitting my oil pan. But it was like only a couple of weeks after that everything was rattling... just like this.


I hit a coconut on the highway is something I never really thought I'd hear. . . Thats funny as hell for some reason.
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Report this Post08-05-2024 12:55 PM Click Here to See the Profile for 82-T/A [At Work]Send a Private Message to 82-T/A [At Work]Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Dukesterpro:

I hit a coconut on the highway is something I never really thought I'd hear. . . Thats funny as hell for some reason.



Hah... yeah. It's not as common here in Tampa where I live now, but when I lived in South Florida (basically Fort Lauderdale / Miami area)... you get a lot of that stuff. Especially on the busy back-roads, or I-95.

The crazy thing is that it's not even people harvesting the coconuts... it's just landscaping trucks that have trimmed up a coconut palm tree, and they dump all the **** into the back of a pick-up truck... and then head out on the highway without any nets or anything. So, coconuts sometimes fall off, and... well... haha... not a problem for most cars, but for a Fiero, that'll send you into a spin.


It gets crazier in the outer parts of Ocala / Orlando area. You have large semi-trucks driving around local roads, filled to the top (overflowing) with oranges and grapefruits. When they make fast turns at intersections (keep in mind there are dozens of them every day going through the same routes), they'll usually lose a few dozen oranges that fly off the top and roll all over the intersection. I was going to the World Money Show once (at the Gaylord Palms), and we were at an intersection where a whole bunch fell off. I quickly grabbed one off the ground, and ran back to the car to eat as a snack before the light turned green. Hah...
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Report this Post08-05-2024 01:21 PM Click Here to See the Profile for Jason88NotchieSend a Private Message to Jason88NotchieEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
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Originally posted by Dukesterpro:


I hit a coconut on the highway is something I never really thought I'd hear. . . Thats funny as hell for some reason.



"I caught my car on fire", was kinda out of left field and funny. Glad things are ok there. Wouldn't have been too funny if not.
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Report this Post08-05-2024 01:49 PM Click Here to See the Profile for DukesterproSend a Private Message to DukesterproEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
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Originally posted by Jason88Notchie:
"I caught my car on fire", was kinda out of left field and funny. Glad things are ok there. Wouldn't have been too funny if not.


I am assuming you are referring to my 84 idle problem post.


On my defense who could have possibly guessed spraying copious amounts of an incredibly flammable liquid on a blistering hot engine would have resulted in a fireball? rofl

TBH at that point I was so frustrated at that car I would have laughed if it had burned up right there. Lucky for her we got it sorted out lol
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