Ok, please bear with me, I will tell what I KNOW

87, L98, auto...

Previously done "things", are moving the IAT up by the air filter, and some of those other "perf mods "

Now, the car runs VERY rich, but, doesnt hunt at idle.

Runs like crap, but, steady...

seems like detonation, and a little backfiring throught mani...

I did notice that the dizzy seems to have wandered a bit... retarded it, helped a bit...

Ok..

Now, that isnt even the main reason its in my garage...

The car is eating ECMs... replace, and all is well...

a month or so later, and its all pissy again...

Read into several threads, about replacement ECMs, and verified that this one seems to be in great PHYSICAL, and visual condition...

NOW, I cannot pull a code(if its throwing any), due to the dash being junk(i hate those things)...

Is there somewhere else, I can run a self test?

I sold my old OBD1 scanner a while back... I just use a multi meter on my bronc...

Basically, my main question is this, and yes, I did search, adn read till my eyes bled...

Is there any issues with the vettes, chaffing, and shorting out the main engine, or main harness?

I noticed some mentions of ground problems...

I am looking for a good starting point, before I yank this damn harness out, and go pin to pin...

There has to be SOMETHING cooking these ECMs...

FOR THE RECORD, other than some maintnance, I have not done any mods to said vehicle, nor diagnosed and/or replaced the ECM issue...

Just looking for some direction, as, I dont know the idosyncrocies of these machines, and every machine has them...

Any more info, ask, I will provide what I can...

I am sure I am forgetting something... long day...

Thanks,
Chase

 

Hey.....First you need to beg borrow or steal a scanner ....Autozone stores in Fla will scan yoour codes.....find a timing light and set that properly too.....there are a LOT of oportunities for wiring problems with corrosion being common.....chafing is possible especially if major work has been done,,,but unlikely if not.....overly rich operation could be a faulty regulator ....O2S....IAC....and try a dedicated ground wire from the ECM to the engine.....other than that find a good psychic with a working crystal ball....much like finding a good working ECM...good luck

 

Fan comes on when iginition is turned to on, fuel metering on the dash is stuck at 99,

CEL DOES NOT WORK now....

Came on when comp was replaced, flashed once, went blank, and car ran like crap...

Help at all?

Chase

 

Get in touch with an ECM rebuilder and ask them if you can send them a defective ECM and have them tell you what circuit failed. This way you will have an idea what circuit is damaging your ECM's. I don't know any rebuilders, you will have to research this. Also, my 87's ECM's would only last about a year (stock, driven every day) and the last one I bought was a GM upgrade and that was about 15 years ago with no further failures.
I would reverse your performance mods one at a time until the engine runs right, what good are they if the engine runs like crap?