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87 Duke DIS Ignition module or Coils? by perceptionist
Started on: 11-16-2007 04:21 PM
Replies: 29
Last post by: perceptionist on 11-29-2007 01:57 PM
perceptionist
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Report this Post11-16-2007 04:21 PM Click Here to See the Profile for perceptionistClick Here to Email perceptionistSend a Private Message to perceptionistDirect Link to This Post
I have noticed my Duke intermittently missing. I used an inductive timing light to determine it was on the #4 cylinder plug wire. The plug wires are new.

I am planning to upgrade my coils to the MSD ones (Fiero Store) anyway but is there a chance this miss could be an issue with the ignition control module? Is there a way to determine this? I am hoping I will only need to replace the coils since the control module is a bit pricy.

As always thank you all so much for your help!

Mike

[This message has been edited by perceptionist (edited 11-16-2007).]

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jaskispyder
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Report this Post11-16-2007 04:45 PM Click Here to See the Profile for jaskispyderSend a Private Message to jaskispyderDirect Link to This Post
miss at idle or at speed? The duke is not the smoothest running engine at idle.

What plugs are you using?

J.
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MstangsBware
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Report this Post11-16-2007 04:47 PM Click Here to See the Profile for MstangsBwareClick Here to Email MstangsBwareSend a Private Message to MstangsBwareDirect Link to This Post
What wires are you running and how many miles on them. I had a new set of wires on my 88 Coupe and it still had a miss. I tracked it down to a bad wire even though it was a new set. Swap wires to see the problem goes with the swap.
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Report this Post11-16-2007 04:57 PM Click Here to See the Profile for perceptionistClick Here to Email perceptionistSend a Private Message to perceptionistDirect Link to This Post
The miss is at idle and at speed but of course more noticeable at idle and low speeds. I am using Autolites but I don't believe the spark plugs would have anything to do with a miss detected in the plug wire.

I will try to swap wires to isolate the miss to a specific wire and report back... Thank you
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Report this Post11-16-2007 05:06 PM Click Here to See the Profile for spark1Send a Private Message to spark1Direct Link to This Post
Also check the plug wire routing. If a wire is near a rough edge of the intake manifold casting, it can arc over. Had that happen once with new wires. The wire wasn't touching, just close.
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Report this Post11-16-2007 11:21 PM Click Here to See the Profile for HudiniClick Here to Email HudiniSend a Private Message to HudiniDirect Link to This Post
Remember the '87 uses a wasted spark system. If the miss were related to the ignition module or coil then it seems #1 would also be affected as both #1 and #4 are fired off that coil. #2 and #3 have their own coil. I'm guessing the plug wire or plug itself on #4.
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Report this Post11-16-2007 11:36 PM Click Here to See the Profile for perceptionistClick Here to Email perceptionistSend a Private Message to perceptionistDirect Link to This Post
I can't imagine the plug would have anything to do with it if you figure I am using the timing light to indicate energy traveling through the wire from the coil to the plug. This energy causes the light to flash with every pulse. When the engine is idling and misses, the miss is represented by a lack of a flash precisely on the miss.

A bad plug would not prevent the energy from traveling from the coil through the wire, would it?

When testing the other 3 wires in the same fashion, the light did not skip on each miss, it remained consistent.

So I took MstangsBware's advise and swapped wires and also tried 1 other good wire. The miss remained on the #4 plug wire.

So at this point I am certain the issue is not in the wire. I am down to blaming either the coil or the Module. Is it possible for half a coil to be good while the other half is having issues?

Tomorrow I plan to swap the position of the 2 coils on the module and see if the miss continues to come from the same coil. This should tell me if it is the coil or the module.... I hope.

[This message has been edited by perceptionist (edited 11-16-2007).]

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Report this Post11-16-2007 11:55 PM Click Here to See the Profile for HudiniClick Here to Email HudiniSend a Private Message to HudiniDirect Link to This Post
A parts store like Autozone or Advance can also test the ignition module. If you go make them test it 3 times to get it toasty hot. If they tell you it's bad then test the new one too......

EDIT: About the plug. The spark will take the path of least resistance so if the #4 plug was the problem then the spark might go to the #1 plug since the coil fires both. Or the problem could be the #1 wire shorting and taking the pulse away from the #4? Might try swapping some more stuff around. At least it's fairly easy to get to everything.

[This message has been edited by Hudini (edited 11-17-2007).]

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Report this Post11-17-2007 12:06 AM Click Here to See the Profile for jscott1Send a Private Message to jscott1Direct Link to This Post
 
quote
Originally posted by Hudini:

Remember the '87 uses a wasted spark system. If the miss were related to the ignition module or coil then it seems #1 would also be affected as both #1 and #4 are fired off that coil.



Maybe not...even though #1 and #4 are fired off the same coil the timing is different. There is still one spark each per cylinder during the ignition cycle. You might be getting the spark for #1 but not for #4.

Before someone tries to correct me let me clarify that although the cylinders are fired in pairs... only one of those cylinders is in the power stroke so the other one is essentially wasted...So #1 and #4 can be firing when #1 is in the power stroke but when #4 gets to the power stroke...maybe a misfire.

[This message has been edited by jscott1 (edited 11-17-2007).]

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perceptionist
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Report this Post11-17-2007 12:56 AM Click Here to See the Profile for perceptionistClick Here to Email perceptionistSend a Private Message to perceptionistDirect Link to This Post
 
quote
Originally posted by jscott1:


although the cylinders are fired in pairs... only one of those cylinders is in the power stroke so the other one is essentially wasted...So #1 and #4 can be firing when #1 is in the power stroke but when #4 gets to the power stroke...maybe a misfire.



So are you saying that if there is an issue with the coil, #4 would be more likely to experience a misfire than #1? I am not sure I understood your explanation, but I want to

Also if it means anything to anyone, I did replace my Crank position sensor last week. The problem I am having existed before that though.

[This message has been edited by perceptionist (edited 11-17-2007).]

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Report this Post11-17-2007 01:44 AM Click Here to See the Profile for uhlanstanClick Here to Email uhlanstanSend a Private Message to uhlanstanDirect Link to This Post
Probably not the module.make sure the coil tower is clean..it is possible to have one coil tower fire and the other weak,because of internal short..If coils are numbered 1& 4 and 2 &3 these are original coils.. a dirty or cracked coil tower will cause short.. I think the coil tightens down on the connectors make sure this is clean ..DO NOT remove module unless you have to..crank magnetic sensor is easy to damage,,,,sensor not as strong as you think it is !! easy to crack,hmmm wonder how I know..use care if you must remove..Pull module straight out at proper angle..If the miss was not present before changing plugs,,you could check plug to make sure it is gapped at .060 ,,easy to smash gap as you try to find hole.. I use an old spark plug boot pushed down on the spark plug to install plugs,, this way you can not cross thread,once threaded in switch to plug socket.. sometime a simple ohms test will show a bad coil tower compare to the other 3

[This message has been edited by uhlanstan (edited 11-17-2007).]

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Report this Post11-17-2007 10:52 AM Click Here to See the Profile for HudiniClick Here to Email HudiniSend a Private Message to HudiniDirect Link to This Post
What I was suggesting is to try swapping #3 and #4 wires. Then #3 and #4 plugs. The #1 and #2 wires, then plugs. (Not allot of work but a PIT lower back bent over the car) If that does not work then pull the coil pack and swap the coils. I'm just trying to suggest a way to check out the individual components before spending any cash.

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Report this Post11-17-2007 01:25 PM Click Here to See the Profile for uhlanstanClick Here to Email uhlanstanSend a Private Message to uhlanstanDirect Link to This Post
Hudini is correct.. remember the spark plug wire and the spark plug become one unit when connected,, a misfire in the spark plug could cause an intermitten spark,,ALLWAYS check the easy stuff first..With a known miss in one cylinder,you of course try another wire first,,then check spark plug,before you move to coil..It seems very unlikely the module or sensor would be bad,if the coil is funtioning on one cylinder,, since both towers fire together..the reason also for checking the plug first ,the condition of the plug tells you about different problems,like if a plug is white there could be a manifold leak,ect.. but you more than likely have a bad coil,or spark plug..after the plug then you check for grease grit trash that could cause the spark to jump,, Never spark the plug wire to the block always have a spark plug in the plug wire to prevent damage to the electronics!!or the spark jumping to your arm
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Report this Post11-17-2007 08:00 PM Click Here to See the Profile for jetmanClick Here to visit jetman's HomePageClick Here to Email jetmanSend a Private Message to jetmanDirect Link to This Post
Did the switch of the coil paks work to help diagnose the difficulties yet?

I'm wondering if one of the coil paks has a small crack in the terminal or if the spark is leaking? My thoughts would be to thoroughly inspect / clean the paks off and use a healthy amount of dielectric grease on the terminals.

Far be it for me to question autolite plugs but I would double check the gap and also try switching two plugs around or changing out for a different fresh plug to see if that makes a difference after the coil switch.

Here's hoping that you got the problem solved.
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perceptionist
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Report this Post11-17-2007 09:26 PM Click Here to See the Profile for perceptionistClick Here to Email perceptionistSend a Private Message to perceptionistDirect Link to This Post
Well it's been a long day. Here is what has been done so far.

I swapped the coils and did the timing light test. I then noticed the light skipping intermittently on each of the 4 wires though the car ran the same as before. I brought the Ignition control module to Autozone for testing, they said it was fine. I then had them check my coils for resistance, they said they were borderline (they are the original coils. I bought 2 new coils and a new coolant temp sensor for the ECM and new plugs.

When I swapped out the plugs I noticed the autolites I was using were platinums. I bought them before reading here that the DIS ignition system doesn't tend to like platinums, so now I am using Autolite non platinums.

I cleaned up the ICM and installed it with the new coils. Also did my first oil/filter change since the new motor was dropped in air filter as well.

Does anyone know what this sensor is for? Could it be at fault for any of these issues?



During the time I was working on the car I left the battery disconnected to ensure reseting the ECM.

In another post ( http://www.fiero.nl/forum/Forum2/HTML/087347.html ) I was concerned about a code 35 that has been haunting me forever even before the new engine. It usually appears when I am idling for longer than like 30-45 seconds. It will go away after I raise the rpms either in neutral or driving. Not sure if this issue is related.

I recently rebuilt the throttle body & replaced the fuel filter. I also replaced all vacuum hoses. Hmmm not that it matters but for the sake of being thorough on what has been done to this car...

water pump:new

serpentine belt:new

Oil pump:new

O2 sensor:new

Clutch & master:new

Clutch pedal:new

EGR:new

Rear brake calipers:rebuilt

Crank position sensor:new

There is also another post regarding how it will not idle on its own without me there touching the gas. But this is only before the car has been warmed up. I thought the coolant temp sensor replacement would have dealt with that. It has been suggested I should check my fuel pressure (which I have yet to do) But if the car runs fine at speed doesn't that clear my fuel pump of any blame?

All this and still missing. Oh and I also saw a couple threads discussing the 87 ECMs had some kind of coating on the circuit board that would shrink over time causing solders on the board to break resulting in small intermittent ignition issues. I removed the center console and saw that the ECM was a re manufactured one so I figured it would not have the same issue as the factory one.

Ok well I think I got it all out Sorry for the extensive rundown, I am just hoping someone out there might be able to use all this info and help me to piece it together in my seemingly futile efforts to get it running smooth.
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Report this Post11-18-2007 05:17 AM Click Here to See the Profile for jscott1Send a Private Message to jscott1Direct Link to This Post
 
quote
Originally posted by perceptionist:

I am not sure I understood your explanation, but I want to



A common misconception about the 4 cylinder DIS is that the coil only fires twice every two revolutions... it fires 4 times just like a regular ole distributor 4 cylinder. The only difference is that you have two coils and each coil silmultaneously fires two cylinders. The catch is that only one of those twp cylinders has compressed fuel in it ready to burn...the other one is on the exhaust stroke, so that spark is wasted. That's why it's called a waste spark system. The only real reason to do it that way is that GM was being cheap and only put 2 coils instead of 4. I guess two coils are better than one, but it's a cheesy setup if you ask me. More modern engines have a separate coil for each cylinder.

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Report this Post11-18-2007 09:06 AM Click Here to See the Profile for jetmanClick Here to visit jetman's HomePageClick Here to Email jetmanSend a Private Message to jetmanDirect Link to This Post
At this point why don't we consider the ignition brick good to go. You mentioned light skipping intermittently on each of the 4 wires in your last post, I'm wondering if anyone here has a sure fire way of testing plug wires or should you take your new ones back (defective?) for a nice set of Delphi Packard wires.

I'm aslo thinking about a slight vacuum leak or a bad TPS sensor but missing is usually ignition related. Sure would be nice to get your hands on an auto scanner to "see" what all the sensors are reading, might give you additional insight to what is going on.
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Report this Post11-18-2007 11:03 AM Click Here to See the Profile for uhlanstanClick Here to Email uhlanstanSend a Private Message to uhlanstanDirect Link to This Post
That is the mass air flow sensor,not very important on the duke ,some parts houses will tell you, you do not have one,, the mass air flow sensor is not so important on the first ecm cars but with obd2 it is vital..A code 35 that flutuates the idle up and down or to high this is an air leak!! I presume the iac was cleaned when you rebuilt the tbi, a sticky injector can also cause this problem//common problems with code 35? (1) vacuum leak (2) high air to fuel (3) Hi fuel pressure or leaky injector (4) low fuel pressure or water (5) IAC faulty(double check all conections to IAC)..This is just a list from code 35.. also check hose from fuel tank to vapor canister,you will see this down close to the fuel filter the new injector cleaners are quite good,,if problem persist ,if the car is driven frequently I would run a can of chevron techron(sic).. I am surprised at the length of time injectors will last,but they do need to be cleaned
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Report this Post11-18-2007 12:58 PM Click Here to See the Profile for fierodeletreClick Here to Email fierodeletreSend a Private Message to fierodeletreDirect Link to This Post
Actually I'm pretty sure that sensor is the IAT or intake air Temp sensor. MAF sensors didn't come out until a little while later. I think the duke would benefit GREATLY from a flow-type rather than a pressure-type feedback system.

My duke does similar things and I share a little bit of your road my friend. My next thing I'm going to check is the complete vacuum system.

Good Luck!

------------------
1984 Fiero SE, White, first love, sold...
1986 Fiero SE 2M6, gold
1988 Fiero 2M4, the Fox
1987 Fiero GT, Blue, 3.4/4T40
Still looking for that perfect CJB 88 GT...

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Report this Post11-18-2007 01:57 PM Click Here to See the Profile for perceptionistClick Here to Email perceptionistSend a Private Message to perceptionistDirect Link to This Post
 
quote
Originally posted by uhlanstan:

also check hose from fuel tank to vapor canister,you will see this down close to the fuel filter the new injector cleaners are quite good,,if problem persist ,if the car is driven frequently I would run a can of chevron techron(sic).. I am surprised at the length of time injectors will last,but they do need to be cleaned


I will check this hose today thanks,

I think this might be that sensor in my picture above. Found at the fiero store...


87-88 4cyl AIR CHARGE TEMP. SENSOR
If your 87 or 88 4 cylinder has a timing knock (detonation under a load), then this sensor could be the culprit.
Part # 66751

Based on that description though I don't think it is causing my problems.

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Report this Post11-18-2007 02:02 PM Click Here to See the Profile for HudiniClick Here to Email HudiniSend a Private Message to HudiniDirect Link to This Post
As fierodeletre said it's the IAT or MAT sensor depending on which parts store you ask. Might want to check the TPS sensor for the idle errors. They are $20 new for the el-cheapo version.
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Report this Post11-18-2007 08:08 PM Click Here to See the Profile for perceptionistClick Here to Email perceptionistSend a Private Message to perceptionistDirect Link to This Post
I did some more investigating and found the wires to the IAC to be corroded about 6 inches from the plug after removing all the tape and wire protector.

2 of the wires were just hanging by 1 strand and the insulation on all 4 wires was pinched exposing the copper. I cut out the bad section of wire and spliced them together.

I then reset the ECM and went for a drive. Now all seems well with the idle, but then the engine was at operating temp. So I need to try to start it cold later.

I am still getting a #35 code but only when I check for codes, its stored in there. I have not seen the SES light come on though since I repaired the wires to the IAC.

I thought disconnecting the battery wire to the ECM would clear this code, maybe there is still an issue causing this code to return?

Well thats where I am at now until I try to start it cold

Oh BTW I just picked up one of these today to check my fuel pressure. I have yet to put it to use...

http://www.actron.com/product_detail.php?pid=16175
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Report this Post11-18-2007 09:45 PM Click Here to See the Profile for perceptionistClick Here to Email perceptionistSend a Private Message to perceptionistDirect Link to This Post
Ok I just went out to try and start it without giving it any gas. It started right up, idled at 500rpm for like 15 seconds then went up to about 1000rpm for 2 seconds then died. I could not get it to start again without giving it gas.

My aim is to get this straightened out so I may install a remote starter to warm up the car unattended.

What is the procedure for testing the MAP sensor? Could any issues with MAP sensor contribute to this?

The car does idle perfectly when it is warmed up, just wont idle unattended when cold.
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Report this Post11-18-2007 10:28 PM Click Here to See the Profile for perceptionistClick Here to Email perceptionistSend a Private Message to perceptionistDirect Link to This Post
Ah yes I just can't seem to call it quits for the evening...

I just removed the MAT sensor and spray cleaned it with carb cleaner, then put fresh thread tape and re installed. Wonderful, Now it will stay started cold!!

When cold it now idles a bit rough at 500 then a couple minutes later the idle will begin to waver back and forth between 500-1100. I sat there while it did this giving it no gas, it continued to waver. By the time the car was at full operating temp and it was still wavering, I turned it off and called it a day.

Whew, at least it's able to warm up on its own now.

Now to isolate the wavering idle issue.... any ideas? MAP? Or possibly replace the MAT altogether? Cleaning it did make a definite difference.

Mike
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Report this Post11-19-2007 12:33 AM Click Here to See the Profile for HudiniClick Here to Email HudiniSend a Private Message to HudiniDirect Link to This Post
Rock Auto sells the MAT (Intake Air Charge Sensor) for $14-$25 depending on brand. Might be just the ticket. The MAP can be found in the junkyard. Just a 1 bar MAP. Nothing special. $32-$45 at Rock Auto new.
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Report this Post11-20-2007 09:56 AM Click Here to See the Profile for uhlanstanClick Here to Email uhlanstanSend a Private Message to uhlanstanDirect Link to This Post
My nomenclature mistake ,it is the MAT sensor,glad to hear you cured part of the problem,,I live in florida so the MAT is not a factor,always rewrap the mat sensor with teflon tape to prevent leakage ,, this is suppose to set code 23 or 25 for V6,might set code on duke but this is not the problem.. The Idle control valve should be cleaned, use Q tips to clean inside T B I(carefull),do not ajust unless there is an obvious problem..you can drop fuse to reset code rather than disconect battery,a faulty map should set a code,disconect hose to map and see if it runs worse..On a duke with idle problems?? pull each plug wire install spark plug in wire and ground plug run on 3 cylinders to see if there is weak cylinder..the tps should read between 035 t0 058(manual 40t50) 1600ohm at idle 5100ohm wot

[This message has been edited by uhlanstan (edited 11-20-2007).]

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Report this Post11-20-2007 11:18 AM Click Here to See the Profile for perceptionistClick Here to Email perceptionistSend a Private Message to perceptionistDirect Link to This Post
Just installed a new MAT or Air Charge Sensor last night. It seemed to help some but I am still getting the code 35 when it is idling for a bit then it goes away when I begin to drive.

It starts and will now idle at 500rpm on its own cold but I still cant trust it completely not to stall unattended while its warming up.

I have read that the rpms when cold should rise to around 1500 or so while warming up then drop down to around 900, Mine stays limping along at 500 when warming up then eventually when it is warm and if it hasn't stalled it will rise and stabilize to 900. What would prevent it from running at a higher rpm during warm up?

I also followed these instructions posted in another thread by 3800superfast to the letter. I did this a few times just to be sure I had it right.


"For the ECM to properly control idle, the throttle stop screw must be set
for "minimum air". This is a process that sets the idle with the IAC
fully
extended. To fully extend the IAC, jumper ALDL pins A and B together (just
like when you check codes) and turn the key on, but do not start the car.
With the key on, not running, and in diags mode, the ECM will keep
trying to
fully extend the IAC. After 30 seconds or so, pull the IAC connector
off the
IAC *before* doing anything else. This will capture the IAC fully extended.

Now pull out the jumper in the ALDL, and start the car. Typically the
"minimum air" idle speed is in the 500 RPM range. I find the car can
bearly
run at 550. So as long as you can get it to idle on its own between 600 &
700 your good. Set the idle using the throttle stop screw. (The engine
should be fully warm to do this.) Now shut the engine off and reconnect the
IAC wires. The ECM does not know where the IAC present position is, so pull
the ECM fuse (or disconnect the battery) for 20-30 seconds. (This will
cause
a complete ECM reset of all learned parameters, including the learned IAC
ones. Then reinstall the ECM fuse.

Turn the key on, wait 10 seconds or so, and turn the key back off. This
will
now reset the IAC to a known key-off "park" position. Now start the
car. The
engine should idle properly under control of the ECM. There are some
learned
values, such as an IAC offset for A/C, etc that need to be learned, but
this
will happen under normal driving conditions. I suggest driving the car
right
away under all conditions. Stop & go, steady cruising over 45 mph, full
throttle, and so on. Pull over a few times and turn the car off, then
restart it. The IAC can only learn X amount of counts with each run
position. If everything else on the engine is in good condition and
operating properly it should be around 900 RPM after coming to a complete
stop with slight variations and improve over time."


Code #35.....Please go away

Thanks,

Mike

[This message has been edited by perceptionist (edited 11-20-2007).]

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Report this Post11-26-2007 12:42 PM Click Here to See the Profile for perceptionistClick Here to Email perceptionistSend a Private Message to perceptionistDirect Link to This Post
I haven't gotten the code 35 (not even stored) for almost a week now until this morning when warming it up. This code was accompanied by a code 42 as well which I have never gotten before. I saw that code had something to do with my Ignition.

My module was tested and passed. 2 New coils. New Crank Position sensor. New Plugs. Wires are fairly new, checked for arcing in the dark.

Considering that I have just about replaced EVERY sensor on this thing except for the IAC motor (Which seems to run fine when checked off the TB in diag mode) and the TPS (which I believe I bought new last year) and I am still having unattended warm up issues.

Due to the broken wires I found going to the IAC recently, I bought an engine wiring harness from the mall here so I can go over it and either use it on my car if salvageable or use it to preferably model a new harness after so I may better route the wiring away from the engine around the perimeter of the engine bay.

ANY tips for making my own harness would be very much appreciated. I am pretty meticulous and can probably figure out all the routing etc... but if there are any issues I would need to know regarding attaching new wires to the large connector that goes to the ECM etc...

Can this large harness connector be purchased new? I have seen at the fiero store several of the engine sensor pigtails are available so no problem there.

If my problem is not in the harness, then I am totally in the dark here.

I did buy a new windshield washer fluid pump, but this did nothing for my cold idle issue
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USFiero
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Report this Post11-27-2007 02:10 AM Click Here to See the Profile for USFieroSend a Private Message to USFieroDirect Link to This Post
check Ogre's cave, don't bother spending the $$ on the MSD coils. You could have a bad new wire. Watch the motor when it's dark and see if there is any arcing. If the module was bad, the car probably wouldn't run. The IAC valve gasket is usually a culprit, as could be a vacuum leak. Check this archived thread, it helped me with my DIS duke.

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Report this Post11-29-2007 01:57 PM Click Here to See the Profile for perceptionistClick Here to Email perceptionistSend a Private Message to perceptionistDirect Link to This Post
I checked for vacuum leaks visually & physically replacing any questionable tubes. I also used the starting fluid mist method around all vacuum tubing & throttle body with no alteration to the idle.

O ring for IAC is new. Also checked in the dark for any arcing along plug wires, none to be found.

I am not getting the code # 35 as often anymore however it does still come up once in a while.

When I start in the morning I get much white smoke and it smells quite rich. Since the engine is new last month and it is usually below freezing in the morning, could the white smoke just be steam? When the car is warmed up, there is no visible smoke out the exhaust.

I have replaced the following this month:

Exhaust manifold
Fuel filter
O2 Sensor
MAP Sensor
Throttle Position Sensor (TPS)
Crank Position Sensor
Coolant Temp Sensor (ECM)
MAT or Air charge sensor
Rebuilt/Cleaned throttle body (this included all associated TB components, FPR etc...)
EGR Valve
PCV Valve
Both Ignition Coils (standard)
Had Ignition control module tested (passed)
Spark Plugs (Autolite #666 Non Platinum)
Air Filter
Damaged wires to IAC repaired


I have a few questions regarding my engines inability to idle cold unattended.

Please note the car idles just fine on its own when warm.

1 - I have yet to replace my IAC but I have read here that it either works or it doesn't, and when it doesn't it is supposed to be unmistakable.

2 - I have not replaced my Ignition control module because it has passed AutoZone's testing. I have also read that this is a component that either works or not with no in between. Is this true?

3 - I still need to check fuel pressure but considering the car runs & idles fine when warm and at speed, could this really have anything to do with it not being able to idle cold unattended...plus the rich condition?

I really need to narrow the possibilities down because with as much as I have done so far, this mystery is getting frustrating.

The only thing I can think of is my wiring harness. I have a used replacement on the way to either install once I check it out, or use it to model a new one after.

Considering everything I have done so far, can anyone think of something I may have overlooked that would cause my issue?

[This message has been edited by perceptionist (edited 11-29-2007).]

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