1G Bad ECU or ECU harness?

[loganflynn294]

Well, to start off, I'm on my third ecu in one year. Last summer the car started running super rich at all times, about 10 to 1 on the wideband. It got so bad that it wouldn't even start anymore. After troubleshooting I found that the ecu was bad. The capacitors had leaked and the board was damaged way beyond repair. I bought a used one and plugged it in without replacing the caps again (dumb move, I know) and it worked great for the rest of the summer, car ran perfect.

When I tried to start the car about two months ago, it wasn't getting any spark. I checked the coil pack, power transistor, cas, isc, battery, alternator, basically everything in the electrical system. Finally I noticed that the stock boost gauge wasn't moving at all with the key on, so I pulled the ecu again and found that this one was even worse. Caps leaked everywhere and completely destroyed this one. So, I bought an eprom that was socketed by ecmtuning and had the caps replaced at the same time. I plugged this one in, and I'm stuck with the same problem; no spark and the factory boost gauge doesn't move at all. I don't think it's getting fuel either, the pump works and my afpr is reading the correct pressure, but the injectors don't seem to be firing. Also, with the key on I don't hear the isc or any relays clicking or making any noise at all. The check engine light comes on when the key is on, but it goes out after about 5 seconds.

Car is basically stock besides a MAFT that was in it when I bought it about 7 years ago. As soon as I get this problem fixed I'll be installing link, e316g, and all the supporting mods that I have collecting dust. If anyone knows how to test an ecu without another car, or maybe which wires on the harness I should be focusing on testing, I would greatly appreciate it. I'd love to be able to drive it before it snows here in Buffalo again .

 

[2ga4gb]

Did the eprom come out of a running car cause if not could be a bad ECU in the first place. Im also pretty sure that 90 ECUs are different then all the rest so it had to come out of a 90.

 

[loganflynn294]

The guy said it was a working ecu. It looks immaculate inside and I can tell that the caps were replaced before they started to leak. He also said it was from a 1990. Even if it wasn't, I'm pretty sure it would still run, I think the tach interface is the only thing that is different. So basically if it wasn't a 90, it should run, but the tach wouldn't work.

 

[steve]

Also, with the key on I don't hear the isc or any relays clicking or making any noise at all. The check engine light comes on when the key is on, but it goes out after about 5 seconds.

So you have basic power up function from the ECU but the ISC sounds dead and may have damaged the ECU. The ISC should rehome when you turn the ECU on.

What's the ECU part number? Eclipse Talon Laser Galant 3000GT Stealth ECU ID Reference

 

[loganflynn294]

Thanks Steve, I'll double check the isc and post back.

 

[2ga4gb]

The guy said it was a working ecu. It looks immaculate inside and I can tell that the caps were replaced before they started to leak. He also said it was from a 1990. Even if it wasn't, I'm pretty sure it would still run, I think the tach interface is the only thing that is different. So basically if it wasn't a 90, it should run, but the tach wouldn't work.

I was under the impression there was some re-wiring/re-pinning that had to be done to retrofit anything besides another 90 ECU.

 

[92AWDHX40]

Look at vfaq.com about ecu swaps its all there 91 into 90 and so forth.

 

[steve]

I was under the impression there was some re-wiring/re-pinning that had to be done to retrofit anything besides another 90 ECU.

Yes for it to work correctly but it will usually start the car even if 6 and 14 aren't swapped correctly.