Ok, car is 87 305 TPI 5 spd. The engine looses spark and won't hardly run. I discovered it's losing spark/power when setting the timing. My timing light quit when the engine started to miss and die out. Goes off at the same exact same time as the engine cuts out, stays on steady when it catches and runs good. Which is few and far between now.

The coil is good, had a spare and no change. Had a spare distributor and no change with it and new pickup coil installed. Cap-rotor-plugs-wires are all good.

When I disconnect the timing wire to set the base timing, the engine runs fine. Well as good as it can with only the base timing and no advance. Turn the engine off and reconnect the timing wire and the trouble starts. I've checked this 5-6 times and it happens every single time. Runs good with the wire off, bad with it connected. A friend of mine loaned me a spare computer to try and no change there either.

I'm thinking that the next item to check would be the ESC module, but can't really find any info on here doing a search that anyone has found it to be causing problems with their car.

Anyone here had problems with the ESC module?

 

Whats the alternator charging at at idle speed? How high is the engine idling?

 

The alternator is charging 13.8 volts. Battery is good. Engine idles fine at 750 with the ESC wire disconnected, but shut the car off and connect the wire and the problems start. It's like the power to the ignition is being turned off and on rapidly.

 

Maybe check your coil connection to the distributor? It might be loose or corroded. My tach acts the same way, and its connector is right beside the coil connector.

 

The weather pack connectors are clean and making a good connection. I've checked out the wires to the coil for a constant 12 power supply, have swapped out modules and distributors since I had spares, swapped coils.

It's something that the computer is telling the ignition to do. I'm thinking maybe the ESC module could be doing it. But not much info I can find here on one or how it fails.

 

Is it throwing any codes?

 

I think the esc hardware in your ecm is internal on the memcal or something. I think even if it was sending lots of false knock the worst that would happen would be that the computer wouldnt give you any advance. It should still have spark but Ive heard stories of people who couldnt start their cars with a bad esc module.

Did the replacement distributer have its own ignition module? Hows the coil? Have you checked all the connections in each circuit including the grounds to make sure theyre solid?

The things that the ecm has control over are the dwell and the spark advance. Reaching here but maybe there is something wrong with the ecm itself that causes the loss of spark, like somehow zeroing the dwell.

 

No codes at all other than when I disconnect the ESC wire.

I'd heard there were TSB's out on the distributors for cracking of the trigger wheel, so since I have a spare distributor I swapped in another one, and a new pickup coil. And I have 2 ignition modules and 2 coils. No change using either of them. I found out that I was losing spark while checking timing. The engine grounds are clean and tight. I've also got an extra ground cable running off the battery post to the body. So grounds don't seem to be the problem. Or am I wrong?

The tach jumps wildly when this happens, and as I'm sure you all well know there seem to be no end of things in these cars that can make that happen. So was knocking things down one by one when I found that the spark was going away with the timing light.

And an update: A buddy brought over a spare computer and I swapped my memcal and chip into it. No difference.

So, maybe memcal, maybe ESC module. Not really sure which way to go next.

 

The tach gets its signal from the energising of the coil by the module so it definatly conferms that there is a problem. Hmm... Im stumped for now.

 

The white wire in the gray connector coming off the ignition coil goes to the tach and the pink wire goes to the ignition. You might want to look at the condition of the wiring and the connectors there.

 

The wiring at the coil looks good. No corroded terminals at all. I also took the wire from the coil to the distributor and checked the resistance. And while I was checking I moved the wire around to see if there were any breaks/bad connections in the wire.

As I understand it, disconnecting the ESC wire removes all computer control from the engine ignition and timing. (Correct me if I'm wrong)

So, assuming this is correct, the distributor, pickup coil, cap, rotor, plug wires, plugs, coil, and power to the coil, and the wiring from the coil to the distributor are good since the engine doesn't miss/stumble with the ESC wire disconnected. It believe it has to be something the ECM is doing. But, what would make it shut off the power intermittently?

From my understanding of the knock retard system, it only retards the timing, not shut off the spark.

And with trying the second computer I have and no change in the problem, that leaves the memcal and chip, along with the ESC module that might be causing the problem. Or am I missing something?????

 

That almost sounds like my problem except for the eletronic spark disabled part (sort of).

My car had hard starts and when it did fire up, it would die just a few seconds afterwards. I was able to get it started with the est wire disconnected but it idled like crap.

It turned out to be a faulty injector.

It can't hurt to check the resistance of the injectors and at least if they're good, that's one less thing to worry about.

Then again, what do I know? I think everything is an injector problem now

Good luck, I know how you feel.

On a side note, what made you want to check the timing?

 

well at least someone understands....i posted in tpi..but my car is doing same thing..i also unhooked the blk/tan timing wire and it doesnt act up..reconnect..cutts out pops even backfired once..i have replaced pick-up coil, coil, cap ,rotor, wires, all connections look good tps voltage good, timing ok, fuel pressure looks good..now what?
max

 

If you have some sort of ALDL software, now would be the time to use it to see what the ecm is doing.

 

Well sorry it took me a little while to respond to everyone's posts, but I've been enjoying driving my car around!! Yes, it's fixed.

Let me try and answer the questions in order.

Scottlb9: Was talking to a buddy and just kind of on a suggestion from him I checked to see what and where the timing was, and discovered that I was losing spark. No particular reason I had to check it, just a desperation move I guess.


madmax57: I went through the same things you did to try and solve the problem, and a few more even. I went over all weather pack connections and made sure they are clean and tight. I also checked all the grounds and made sure they were tight. But.........I didn't pull every single ground apart and inspect the connections for corrision. And that's exactly what I found and repaired that cured ALL my problems.

On the left rear cylinder head is a double tan wire bolted to the cylinder head with a stud/nut arrangement. I't hard to see, but pull the wiring harness up and you can see it easily. The nut was tight, very tight in fact. But the crimp on the ring connector had a corroded connection. I only found this out after totally disconnectiing the wire and inspecting it with a lighted magnifier. It's a pain to get to, but worth the effort to check. Get your 9/16" wrench out and check it now before going any further. This just might be the cause of all your problems like it was mine.

Anyway I quickly and easily cut the old connector off and crimped/soldered a new one on and the problem was completely cured!!! No missing, stumbing, backfiring, nothing. The only problem I have now is that during one of the backfires I beleive my MAF was damaged. I'm getting a code 36 bunoff error. I have a buddy that is going to loan me a spare MAF sensor and I'll run it and see if the code 36 goes away.

I'm not real happy that I lost my MAF sensor, but 2 days ago I'd have paid $500 to ANYONE who could have fixed the car. Now a $120 MAF seems cheap to me.

Good luck to you and let me know if the ground on the cyl. head is tight or not.

Dan

 

So it was as simple as the chassis ground being bad? Glad to hear you fixed it.

 

Well apparently I'm told this was the computer and ESC ground wire.

Looking back on it, the no starts, hitting bumps in the road and the engine missing, all can be explained by this poor ground connection. I don't even want to think about how much I spent trying to find this problem when a $.15 connecter and some solder cured it.

 

Way to keep it in perspective

And if your significant other that constantly nags you for working on the car on such a beautiful day asks what are you doing this time...

You could tell her that you're making 380 bucks

(I'm sorry, I think I just super-imposed my life onto yours )

Scott

 

Nah, wife knows how much I love this car. Had it for 18 years now. And, she knows it gets 20-22 mpg in the city, where as my big block pickup gets 8