I have an 86 2.8 V6 (engine is from an 86).


Car had been running fine untill 3 days ago. I made a quick errand and then jumped back in the car to drive away when the check engine light came on and the car lost about 80% of it's power. I was able to limp it home about 2 miles away and the car drove terrible stumbling, sputtering, no power.

When I checked the code only the code 42 came up. So I checked the wires, ignition module (2 years old max) and made sure all grounds and connections were good. The check engine light then went off and the car drove better for about 5 miles. The check engine light never has come back on, but the car is now dead. It will start, but it won't idle, smells of fuel, and I can hardly get it to move, it just sputters, stumbles.

Anyone have ideas of what it could be. I bought a new NAPA ignition module and it made no difference. I don't think that is the problem. If I swap either coil that I have that does'nt seem to help any.

Have you checked the spark plug wires for any breaks or shorting?

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www.fierodomain.com
Your guide to the Online Fiero Community, always under construction

Check/replace your pigtail connector to it. Check all the distributor components. Also as mentioned above check/replace your plug wires--check at night to see if their arching on you...

Code 42 means that the ECM isn't receiving a valid ignition reference pulse from the ignition module. Bad connections on the 4-pin connector at the distributor can cause this, as can a bad ignition module or a badly mounted module - it grounds through the screws, they must be clean and tight.

But this can also be caused by a noisy signal at the ECM. This could be caused by bad engine or ECM grounds, wrong spark plug wires or spark plugs (they NEED to be radio suppresion type) - or some strange device or wiring that's causing the voltage to fluctuate (radio transmitter, big stereo, ?)

I have MSD wires that have about 6k miles on them. The spark plugs are platinum +4's that I replaced from Champion plugs that cracked on me. This was done about 3 month's ago.

I checked all the wire connection to the distributer, but will cehck the wires for cracks or something.

I feel stumped because I just replaced the spark plugs, and the wires are good quality ones, but something keeps happening to my ignition components. It seems my problems with the car steems from either a module failure or bad plugs, wires. My guess is because of too much heat buildup as I drive in slow traffic daily.


Thanks for the replies.

Are you using the ac/delco/gm/brand modual & white heat sink compound. You may want to pull a couple plugs out to have a look, they paint a pretty good story of whats going on..

The module I had in the car was a GM module (rebuilt) from NAPA. It included a heat shield, and I used the white compound. This module has run well for about 2 years with no problems like I used to have with Autozone components.

I will check on everyone's suggestions in about 2 hours. My car is stuck in another part of San Diego.

the pickup coil in the dist could be bad. if the 2 wire connector to the module is crumbling, likely so is the the pickup coil itself. they can be ohm'd out, 750-1500 ohms is the god range according to the book.
you need to pull the dist on the 6 to replace it.

I just pulled the distributor off of mine this morning and you wouldn't believe the amount of corrosion that was in there and it was still sort of running.
In my case the problem turned out to be my ign module.

i dont get a check engine light but my aldl shorter showed a code 42 but like i said never seen the check engine light on....? im gonna disconnect the battery and see if the code comes back

One other thing, how are the grounds on the engine? Is it well grounded to the frame?

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www.fierodomain.com
Your guide to the Online Fiero Community, always under construction

The grounds on the engine were cleaned up 2x in the last year. Once by me, once by a mechanic.


My distributer is not very old, and the pickup coil comes with it, right?. At least I thought it does. I know that 2 pin connection looks almost white because of heat. It's supposed to be red. Should I try and buy a new pickup coil from Fiero Store?

Let's try something else before you go any further. Look at the junction block just behind the battery - there's a thick orange wire there with an inline connector in it.

Disconnect that connector, wait about 20 seconds then connect it back up. That'll clear all the stored codes and learned tuning from the ECM.

It may run badly when you start it after this - go for a drive and it'll relearn the correct tuning in about 15 miles.

Now, see if the code 42 ever comes back. I suspect it won't.

Your’s could be a common problem and don’t cost anything to check.
Try this:
Watch the tach when cranking if it don’t move you're not getting pulses from the distributor. If so, it could be a faulty module in it or more likely simply corroded connectors at the base of the distributor. Reseating those connectors a few times could clean the pins some and also do the same to the connectors on the coil etc. These cars are old, and old connectors corrode. Such can also manifest itself as intermittent misfires, and engine cutouts.
BTW: lots of folks keep replacing modules and coils thinking they are bad because the new ones FIXED the problem, when in actuality the fact that they simply unpluged the connectors and repluged them into the new unit cleaned the contacts enough to make it work again, at least for a while. It's smart, to replace them with new ones. Cliphouse.com has them.

I have connected and reconnected several times now all connections that pertain to the module itself, and coil. I don't believe it comes from a lack of not reseating. The tach does move when cranking and it works when the car turns on for about 5 seconds.


I cannot keep the car running to drive it anywhere, it starts fine has seizures and dies within 5-10 seconds. I pulled the fuse to the ecm that should reset it, correct?

Yes that will re-set the ecm, lets step back a little , any problems before this? Any thing that was replaced in the way of fuel system components? Any other work done on the engine at all?

No other engine work has been done. The only other problem I have is that my fuel gauge has been one tick off for about 4 years now. The car should not be out of gas though.


The car had been running well untill I turned it on after running into the post office for 10 minutes. Right when I turned it on the code 42 appeared from the check engine light. The car ran terribly after that, and now after I reseated the module and rechecked my spark plug wires the car ran about 80% better, for about 3 miles and then crapped out completely. I cannot get the car to move now because it won't stay firing.

I will repost in 2 hours when I get back from work.

yes the coil does come with the dist.
I replaced mine with one from the fs. took car off road, sat 3 years, back on road, in 6 months the pickup coil was dead.
you can get for about 12$ at autozone, same one. meter yours out. disconnect it from the module, and stick a decent digital meter on it. if it is over 1500 or less than 750, it could be the problem as it is out of spec, and may be creating false signals.
you said you see tach pulses, do they appear normal for how the motor is cranking or when it does run, for that short time?
does it back fire at all when it does run or tries to start?
have you looked at the spark color? put a plug on the coil wire, and get it so the bas is grounded. have someone crank the car, it should be a deep blue color center with some white halo. if it is orange, it is weak, and may be the problem. as was said verify those connections to the module, the pign coil and the pickup. look in hte female plug ends for corrosion. instpect the wiring there for thin areas that might indicate a break.

The problem now is the car will not turn over. It cranks and won't start. I just put in new spark plug wires and made no difference. I changed my coil for another one I have and made no difference. I do not have connection problems, all of the stuff is 1 year old. This is why I am getting fed up with this car. My ignition components go out to often. I assume it's the heat, and the fact the car has 160K miles on it.

quote Originally posted by blkpearl: I pulled the fuse to the ecm that should reset it, correct?

No, not correct. The ECM has a separate power feed that maintains its memory - that's the orange wire I was talking about a few messages back. If you can't find the connector in the orange wire, disconnect the battery instead.

Pulling the ECM fuse WILL NOT reset the ECM.

I followed you're instructions to reset the ECM.

Again thanks everyone for their help.

Car has died again. I replaced the distributer again with Napa and once installed the car did startup. Drove it 200 yards and then started the seizures again, thus dying. The car at least starts at this point. I need to figure out what the heck this is.

I replaced the Spark plug wires.
Replaced Distributer including module.
Connections all work.
Spark plugs are Bosch Platinum +4 at 4 month's old.


Ignition coil is original GM. Could it be bad? Help, this thing is killin' me.

Check to see where your timing is, if it is off that could be throwing a code 42 and be the cause of the power loss.
Most of what is happening is the computer is makeing adjustments for the timing being set off but can not compensate once the RPM's reach a certain level. Also if timing has not been changed and is off your timing gears may have slipped causeing the timing to be off. I know this becasuse I got a code 42 years ago and the damn thing drove me nuts untill someone suggested I check the timing on my car and I discovered that it had moved and the chain was at fault.

Thanks for the suggestion.