Despite the 97F+ temperatures and the lack of A/C I decided to drive my Indy to work for only the 2nd time in it's life, Well on the way home I suddenly see Lots of smoke billowing from the center console...I'm like HOLY CRAP! I need to bail out of this puppy or what?!? But before I can do that the smoke subsides and I can tells it's the smell of electronics burning.

It turns out my ECM is smoked, and now it won't start on it's own...I can use starting fluid and get it going, but the ECM is obviously damaged...my Idle is way too high as well. Any body know if the 85 4 cyl ECM is the same? I have one of those as a spare, if not, then I need an 84 ECM.

I'm getting tired of the 84 catching on fire, but so far no engine fires, but I still haven't got my oil leaks plugged well enough so that's always a possibility.

I have an 84 4spd ecm I can give you, not certain if it is still good. I don't have a 4cyl anymore to test it.

quote Originally posted by Xanth: I have an 84 4spd ecm I can give you, not certain if it is still good. I don't have a 4cyl anymore to test it.

pm sent

Were you able to drive it home?

Hell of a title to read first thing on a Saturday morning.
I was going to start one of mine today…I may rethink that.

I wish I had an 84 Indy.
I take that back.....

I wish I had an 84 Indy AND a unfinished chop top!

come on Jon, let's get SOMETHING up and ready for the RRR or gbarf....

I'm the chump that missed winning the 27K mile Indy on eBay last week by $92.....Indy threads make me misty eyed right now <sniff>

I should be driving back from Tucson today....BUT NOOOO!!! I'm sitting here in front of my computer typing and feeling sorry for myself....

Glad to hear your Indy didn't go up in flames. Now might be a good time to just give up on it and put it on a car hauler and ship it to El Paso.... I'll be glad to pick it up when it arrives. Just leave the signed title stashed under the driver's seat.

Part of the problem may be the wiring harness. If you have frayed or loose wires then it can cause shorts in the ECM as voltage spikes are likely. And I know only too well how nasty '84 wiring is! Start with the starter and the fusable links therein.

Good luck.

Luckily I made it home under my own power...good thing I didn't shut it down, because it won't start on it's own now. But once started the Idle is like at 2500 RPM but that didin't affect me on the highway. As soon as I replace the ECM, and like three other things, I'm going to try driving it again, on little shake down cruises. Bringing a car back after sitting for a decade is much harder than I imagined.

Revin - as for the Ruckes and G-Barf, my GT is running, I just don't trust your ignition module anymore. As soon as I change it out I can drive it again.

Got the replacement ECM but it won't power up, (no check engine light).

I have a question over in tech, but no answers yet, can someone help me find the Fusible link "F"? It's supposed to be near the battery, but I can't find it.

The engine runs, but it won't start. (huh?)

If I spray ether into the throttle body it will start right up, but the pump will not prime from the ECM and even if I prime the pump manually by jumping the "G" connector on the ALCL, (pump runs) it won't start on it's own.

I'm getting tired of this crazy 84 wiring...can anybody help??

Mine just quit on me about a month ago and no power what so ever. Pull the insulation back away from around where the starter is and check the wires to it. Mine burned into before the fusable link there. You almost have to stand on your head I think to see where it is. At least that is the story from my shop on what they repaired. Fuseable link was still good.

Well, I don't know how different 84 is than my 88, but I had a similar problem. No start, would turn over and fire if I sprayed gas or starting fluid into the throttle body. No check engine light, either.

In my case, it was an open in the circuit that feeds power to the ECM. I think it's Ckt 240 - it's an orange wire that goes straight to a fuseable link (probably link F that you're looking for). This wire should have 12V+ at all times. On my ECM, there are two of these wires connecting to the ECM - one on each of the 2 ECM plugs. I forget what position it is on the plug, but it's on the outside corner, and it's orange - so that should narrow it down.

If the ECM isn't getting power, the injectors never fire. You still get spark from the distributor, though.

I was able to rig up a temp fix on my car by taking the hot wire from the cigar lighter and running that to both orange wires on the ECM. The cigar lighter is also on an orange wire that's 12V+ at all times, but it's on a different fused circuit. That got the car running until I could trace down where the break was.

Here's the link to my thread: https://www.fiero.nl/forum/A...010924-2-009156.html
Some great troubleshooting steps from the shop manual that helped me figure it out.

[This message has been edited by Formula88 (edited 09-05-2007).]

quote Originally posted by Formula88: Well, I don't know how different 84 is than my 88, but I had a similar problem. No start, would turn over and fire if I sprayed gas or starting fluid into the throttle body. No check engine light, either. In my case, it was an open in the circuit that feeds power to the ECM. I think it's Ckt 240 - it's an orange wire that goes straight to a fuseable link (probably link F that you're looking for). ...

YES! This is exactly what I'm experiencing. But hte mosquitos chased me back inside before I could find that fusible link. I could hot wire the ECM and see if I can get it to start, but I'm sure that's what happened.

But the other danger is I don't know what caused the ECM to short out in the first place. Aren't there three or 4 relays that if they go bad they'll take the ECM with it? I need to check out those relays before I power up the new ECM.

On the 84 I've heard the IAC valve can be a problem and kill the ECM without throwing a check engine light. I believe Whitecloud had that problem, according to his factory manual the 84's had no error code for the IAC but a bad one could kill the ecm.

[This message has been edited by Xanth (edited 09-05-2007).]

i have a known good 84 ecm. pm sent.

quote Originally posted by jscott1: But the other danger is I don't know what caused the ECM to short out in the first place. Aren't there three or 4 relays that if they go bad they'll take the ECM with it? I need to check out those relays before I power up the new ECM.

Are you sure the ECM is fried? In my case it just wasn't getting power, so swapping in a good ECM didn't help. I was able to test mine in another car, though.

jscott1, wow. I did not see you were having troubles. I don't know what you have to fix but I have an almost complete 84 SE (duke). I am parting it out. I gave maryjane some stuff and also fierofetish. Neither took any electrical stuff. Just let me know what you need.

Here is the verdict...

The ECM was definitely smoked...The car was full of electrical burning smell and the ECM reeks of it.

Somehow yesterday I failed to see this, but Fusible link F was definitely smoked as well...



I don't know the root cause, but to be safe I replaced the fuel pump relay and checked the A/C relay to make sure they were good. The relays get power directly from the ECM and if they are shorted they will short out the ECM.

And after replacing Link F, with the "new" ECM....

She fired right up. Ran it for 10 to 15 minutes and nothing smoked... Started it several times and all seems to be well. It's purring like a kitten

My guess is the old ECM just died of old age.

PM coming at you.

Ouch.....glad it all worked out OK.