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Fuel, Air, Spark but no Bang by Intel
Started on: 05-13-2023 02:06 PM
Replies: 21 (379 views)
Last post by: greenturnedblue on 05-23-2023 11:37 PM
Intel
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Report this Post05-13-2023 02:06 PM Click Here to See the Profile for IntelSend a Private Message to IntelEdit/Delete MessageReply w/QuoteDirect Link to This Post
Hi there, old member here from the past but now resurrected.

I've had my 87 Fiero 2.8 in storage for a couple of years (a startup and run until operating temp every now and then) it ran fine when parked with new dist, plugs, wires, module (GM),

Now It's time to take it out. But... can't get it to start. It turns over evenly but not a single hit. Not a poff or a pft...nothing.

Here's what I have done:

- Pumped out all old stale fuel through shrader port. +12v to ALDL connector. Put 20L of fresh fuel in and pumped out some more so it's fresh in the fuel rail and lines.
- Checked fuel pressure: 60 psi on fuel pump only (a little high?, I have an adjustable fuel pressure regulator) and around 40psi when cranking.
- Fuel pump primes fine when key on.
- I smell fuel when I crank and when I check the plugs they all have some fuel on them, but not super wet. They all spark nice and bright.
- No mouse or rat nest in the intake or exhaust.
- Checked the dist, and swapped ignition module to another spare delco. Dist, cap, rotor, wires is the newer type and have only 200 miles on it. But since there's good spark I dont think this is the issue.
- I have good oil pressure when cranking.
- Checked all fuses, relays and coil wires.
- Checked all visible wires in case a mouse chewed on it.
- Fresh battery
- Tested with another stock coil, now running an MSD Blaster.
- I also just for sanity checked plug wire order, but it's correct, they were all marked correctyl when I installed them.

Left to do:

- Check/reset the timing, but why, it ran when parked. Not easy to do when it doesn't start.
- Check my coil with an ohm meter in case the spark is weak.
- Fuel injectors: Just ordered a noid light. Might be clogged or something. The ethanol in the fuel here might be messing with them. I have a spare set of reconditioned/matched injectors but prefer swaping those in my own garage.
- Try starting fluid/spray to check if ignition is working at all.
- Swap out ECM, I have a spare one with stock eprom in it. Right now I have a Memcal with EGR-delete from Fiero Addiction and been running that since 2008 with egr system removed. The other ECM should work but would throw an EGR error.

I'm soon running out of stuff to try, so any pointers is appreciated.
It's extra fun because my storage garage is 6 miles from home and no power or tools there so I have to bring everything from my regular garage.

[This message has been edited by Intel (edited 05-13-2023).]

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Patrick
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Report this Post05-13-2023 05:18 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 Intel:

Hi there, old member here from the past but now resurrected.


Welcome back!

 
quote
Originally posted by Intel:

...when I check the plugs... They all spark nice and bright.


That really tells us next to nothing, as even a weak spark will have no problem jumping a 0.045" gap outside of a pressurized combustion chamber.

A healthy spark will easily snap across a 0.25" gap to ground under atmospheric pressure.
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Report this Post05-13-2023 05:33 PM Click Here to See the Profile for IntelSend a Private Message to IntelEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Patrick:

That really tells us next to nothing, as even a weak spark will have no problem jumping a 0.045" gap outside of a pressurized combustion chamber.

A healthy spark will easily snap across a 0.25" gap to ground under atmospheric pressure.



Well that's more of an educated guess I made based upon on all the vehicles I've fiddled with through my 50 years. I know a weak spark when I see (or hear) one. This one is not weak. I also tried another coil than my MSD blaster (forgot to mention). Same result.
Besides eyballing the spark or using a spark-plug light I really dont know how to check spark strength. Just putting a nail in the plug boot and see if it jumps a good distance? MIght have to test that. My old stock coil could be bad too...

Adding to my list that I shoud test my coil with an ohm meter.

[This message has been edited by Intel (edited 05-13-2023).]

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Report this Post05-13-2023 06:28 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 Intel:

Well that's more of an educated guess I made based upon on all the vehicles I've fiddled with through my 50 years.


Through my 67 years, I've "fiddled" on vehicles for 53 of them.

 
quote
Originally posted by Intel:

Besides eyballing the spark or using a spark-plug light I really dont know how to check spark strength. Just putting a nail in the plug boot and see if it jumps a good distance?


Simple. Use a Phillips screwdriver with an insulated handle. Stick the end of the screwdriver into a spark plug lead, and hold the shaft of the screwdriver a quarter inch away from something metal on the engine. Make sure your hand is well away from the metal shaft of the screwdriver! Get someone to crank the engine while you're in position. Nothing to it.
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Report this Post05-13-2023 06:37 PM Click Here to See the Profile for IntelSend a Private Message to IntelEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Patrick:

Simple. Use a Phillips screwdriver with an insulated handle. Stick the end of the screwdriver into a spark plug lead, and hold the shaft of the screwdriver a quarter inch away from something metal on the engine. Make sure your hand is well away from the metal shaft of the screwdriver! Get someone to crank the engine while you're in position. Nothing to it.


I'll add that to my check/"fiddle" list for tomorrow. Thanks

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Report this Post05-13-2023 11:04 PM Click Here to See the Profile for shemdoggSend a Private Message to shemdoggEdit/Delete MessageReply w/QuoteDirect Link to This Post
Check injector fuses first. Spray some starting fluid in the throttle body and try to keep it running for a few mins.

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Report this Post05-14-2023 01:33 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 shemdogg:

Check injector fuses first.


I didn't suggest that here, as I did in your thread, due to what the OP posted earlier...

 
quote
Originally posted by Intel:

- I smell fuel when I crank and when I check the plugs they all have some fuel on them, but not super wet.

- Checked all fuses, relays and coil wires.


[This message has been edited by Patrick (edited 05-14-2023).]

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Report this Post05-14-2023 12:23 PM Click Here to See the Profile for IntelSend a Private Message to IntelEdit/Delete MessageReply w/QuoteDirect Link to This Post
Well I sorted it out.

Turned out the ignition was WAY off!!

I really dont know how this can happen because just before I put the car in storage I drove a pretty long trip along the coast, fueled it up, and into the garage, the timing was perfect back then.

A year before that I swapped the old rusty original style dist for a newer style, because the pickup coil was bad and the shaft had some slop.

When I installed the new dist I went by the book, cylinder 1 at TDC, Big white timing mark at zero. Rotor pointing at Pole 1 (roughly 4 a clock or at the right dist-cap bolt). Everything lined up like in the drawings I've seen here. Marked old dist and rotor position took photos.
Swaped it out, put new in exactly as old one.
Set the timing to 12 degrees with ALDL a+b shorted, runs like a champ.

How can it be this off after storage? I've had the battery off the car the whole time so the ECM is reset.

Now I had to move all my wires 2 poles counter clockwise to get in the ballpark where something started to ignite (got a backfire so loud the neighbors thought the hunting season was on). After a little playing around (with the ALDL shorted) I got it at 12 degrees. Runs great now.

I got a much better garage this month, much closer, without critters and I have lights and power. Here's my precious getting a quick wash today. First time rolling since 2017.

[This message has been edited by Intel (edited 05-14-2023).]

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Report this Post05-14-2023 05:07 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 Intel:

Turned out the ignition was WAY off!!


Well yeah, ignition timing is critical... but no one's going to mention that when they read the following...

 
quote
Originally posted by Intel:

...it ran fine when parked with new dist, plugs, wires, module (GM),


Only four things will affect the ignition timing.

#1) the distributor body has spun, which affects the position of the distributor cap relative to the rotor
#2) the distributor body has moved up or down, which affects the position of the rotor relative to the distributor cap
#3) the timing chain is so loose that it jumped a sprocket or two (which of course would also affect camshaft timing)
#4) there are mischievous storage garage pysslings which like to mess with an engine's ignition timing
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Report this Post05-14-2023 05:27 PM Click Here to See the Profile for IntelSend a Private Message to IntelEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Patrick:

Only four things will affect the ignition timing.

#1) the distributor body has spun, which affects the position of the distributor cap relative to the rotor
#2) the distributor body has moved up or down, which affects the position of the rotor relative to the distributor cap
#3) the timing chain is so loose that it jumped a sprocket or two (which of course would also affect camshaft timing)
#4) there are mischievous storage garage pysslings which like to mess with an engine's ignition timing


The spun dist could be possible, but then it can't move that far. It would have torn the wires going to the ign module. I'm always going over the bolts when I've wrenched on it but it's possible I forgot to tighten it when I set the timing.

The car only have 24000 miles so the chain shouldn't be stretched but you never know. I have a fairly new steel impeller water pump on it and I'm not going to rip it off to have a look at the chain. What ever happens, happens.

I'm starting to lean towards the pysslings... 😂

[This message has been edited by Intel (edited 05-14-2023).]

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Report this Post05-14-2023 06:01 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 Intel:

The spun dist could be possible, but then it can't move that far.


It doesn't need to rotate much to completely throw off the timing.

I didn't understand the following. Why did you feel the need to move the location of the spark plug leads in the distributor cap? All you had to do was to reposition the rotor (by lifting the distributor up just far enough to disengage the gear).

 
quote
Originally posted by Intel:

I had to move all my wires 2 poles counter clockwise to get in the ballpark where something started to ignite (got a backfire so loud the neighbors thought the hunting season was on). After a little playing around (with the ALDL shorted) I got it at 12 degrees. Runs great now.




 
quote
Originally posted by Intel:

- Check/reset the timing, but why, it ran when parked. Not easy to do when it doesn't start.


You may wish to have a look at how to set the initial static timing.

[This message has been edited by Patrick (edited 05-14-2023).]

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Report this Post05-14-2023 06:16 PM Click Here to See the Profile for IntelSend a Private Message to IntelEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Patrick:

You may wish to have a look at how to set the initial static timing.





I know but I didn't have a 15 mm wrench in that garage.
I forgot my tools in my daily driver that my wife took to work. So I drove out to the Fiero garage in my Corvette with only a Fluke multimeter and a Leatherman.
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Report this Post05-14-2023 06:50 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 Intel:

So I drove out to the Fiero garage in my Corvette with only a Fluke multimeter and a Leatherman.


Should've been enough for a complete system analysis and engine rebuild.

Anyway, you got it running.

I got my '84 running yesterday after it had sat unstarted for three years... with three year old gas in the tank. Charged up the battery beforehand, and it basically started right up. Fortunately, the gas here doesn't appear to turn into a gummy substance like what I've heard reported happens to gasoline in the States.
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Report this Post05-15-2023 04:55 PM 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:
I got my '84 running yesterday after it had sat unstarted for three years... with three year old gas in the tank. Charged up the battery beforehand, and it basically started right up. Fortunately, the gas here doesn't appear to turn into a gummy substance like what I've heard reported happens to gasoline in the States.


I guess the corn lobby isn't as influential in Canada.
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Report this Post05-15-2023 06:07 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:

I guess the corn lobby isn't as influential in Canada.


Corn syrup would definitely gum things up.

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Report this Post05-16-2023 10:34 AM Click Here to See the Profile for IntelSend a Private Message to IntelEdit/Delete MessageReply w/QuoteDirect Link to This Post
Okay, so I just found out why my timing is totally off.

My harmonic balancer must be slipping. I tried the piston stop bolt in the spark plug hole 1 method, cranked clockwise until stop. Set mark at zero, cranked anticlockwise till stop, set another mark at zero. Right between these two marks should be my timing mark..... it's not even near!

From the pictures I've seen of a stock fiero balancer the mark should be a few degrees (-) from the axle keyway. My mark is at -90 degrees.
I guess the low mileage doesnt matter anymore, age takes it's toll on things.

So I guess I'll be trying to source a new one and then use this metod to find my timing mark since most harmonic balancers marks nowadays doesn't line up with the fieros. Oh the fun....
Are the fiero-stores HB's any good? I have bought quite a lot from the before, mostly because I get parts that I know will fit my car and returning parts is not possible for me. Would cost more in shipping than the part. Buying locally is also not a viable option. Last time I looked something up they wanted $250 for a set of Taylor ignition wires.

Mostly writing it here if anyone searches around for a similar problem.

At least the 40 liters of fuel I emptied from the fuel tank is good, after 8 years! I put it in my motorcycle that was out of gas and it runs just fine. Maybe it matters that I "spoiled" my Fiero with the Shell V-Power "gimmick". The E10 we have now I've been told goes bad after 2 years or so.

[This message has been edited by Intel (edited 05-16-2023).]

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Report this Post05-16-2023 11:01 AM Click Here to See the Profile for ArthurPealeSend a Private Message to ArthurPealeEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Intel:

Okay, so I just found out why my timing is totally off.


A slipping balancer wouldn't affect a slipping timing chain - but, sudden tension from starting might affect it, depending on the wear.

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Report this Post05-16-2023 11:36 AM Click Here to See the Profile for zkhenningsSend a Private Message to zkhenningsEdit/Delete MessageReply w/QuoteDirect Link to This Post
Someone must have messed with it, no way it goes from running to not running while sitting due to timing being out. I would imagine clogged fuel things or stuck injectors, or mice have been nibbling at wires.

You can use a coat hanger or equivalent and put it in cyl 1 and rotate the engine by hand to find TDC, it will not be perfect without a dial indicator or other precision tool but should be able to get you close enough that you can mark a new 3.4 balancer (which I think are more common) at TDC ish and at least get it running. There may be something on this forum somewhere that give you a concrete measurement of where to mark the balancer.
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Report this Post05-16-2023 12:01 PM Click Here to See the Profile for IntelSend a Private Message to IntelEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by zkhennings:

Someone must have messed with it, no way it goes from running to not running while sitting due to timing being out. I would imagine clogged fuel things or stuck injectors, or mice have been nibbling at wires.

You can use a coat hanger or equivalent and put it in cyl 1 and rotate the engine by hand to find TDC, it will not be perfect without a dial indicator or other precision tool but should be able to get you close enough that you can mark a new 3.4 balancer (which I think are more common) at TDC ish and at least get it running. There may be something on this forum somewhere that give you a concrete measurement of where to mark the balancer.


It's the running to not running thing I struggle with the most.
Even if I set the timing "wrong" all those years ago when I swapped the dist, it still ran fine when parked and the car was in the middle of nowhere in a barn, locked, with battery out.

Is there any tell tales of a loose chain? There is no play in the harmonic balancer, there is no weird idle, no knocking in there that I can hear with my mechanics stethoscope.
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Report this Post05-16-2023 12:50 PM Click Here to See the Profile for ArthurPealeSend a Private Message to ArthurPealeEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Intel:

Is there any tell tales of a loose chain? There is no play in the harmonic balancer, there is no weird idle, no knocking in there that I can hear with my mechanics stethoscope.


Without removing the timing cover ? Regrettably, that's a question I can't answer.

When you re-timed it, what steps did you take? How far off was it ?
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Report this Post05-16-2023 06:21 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 Intel:

Is there any tell tales of a loose chain?


When the crankshaft is rotated backwards (using a wrench on the front), the more degrees it rotates before the distributor rotor starts to move, the looser the timing chain is. A certain number of degrees is acceptable. Have a look Here.

But I don't think what you're experiencing is a loose timing chain. Get a good harmonic balancer, time the ignition properly, and see where you stand.

[This message has been edited by Patrick (edited 05-16-2023).]

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Report this Post05-23-2023 11:37 PM Click Here to See the Profile for greenturnedblueSend a Private Message to greenturnedblueEdit/Delete MessageReply w/QuoteDirect Link to This Post
BTW, Dorman 594-013 Harmonic Balancer is a direct fit, but you will need to etch a new line in for TDC
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