1G Burnt ECU

[boostedawdtsi]

Ok here is my problem, maybe someone can help me out?

I have a 92 Eagle Talon awd turbo. It's been sitting for like 9 months waiting on tranny to be put in. I out the tranny in get everything going and a few weeks late maybe 2 or 3 weeks. I smell a burning smell on my way to work, I think its the radio so I unplug it and throw it in the back. When I got home later the afternoon I did further inspection and I find out my ECU is burnt up, car still runs, I don't know how good it runs because my datalogger isn't working for some reason.

So I thought the problem was because its just old and the caps leaked and made the chip burn up. So I buy a used one, I got it today. Plug the new ECU in and after about 2 minutes I see smoke coming from the case so I imediatly turn off the car.

So here is my questions. What would cause a certain chip to burn up? What do the chips in the pics below that are inside the square I drew in the pic below do?

I was thinking maybe it was a short so I included a pic of my wiring harness that connects to the ECU. I have an Apexi turbo timer and it asks to connect to the O2 wire so that was done and the ground is tapped for the turbo timer.

Please help I don't know what to do..

<img src="http://images.cardomain.com/member_images/11/web/455000-455999/455233_25_full.jpg">
<img src="http://images.cardomain.com/member_images/11/web/455000-455999/455233_24_full.jpg">
<img src="http://images.cardomain.com/member_images/11/web/455000-455999/455233_27_full.jpg">

 

[LightningGSX]

IIRC thats an output driver for the Idle stepper, check for shorts/high current draw in the ISC.

 

[boostedawdtsi]

The car is idling kind of funny, stays at around 1100 rpms but it does move around to 1200 or 1300 and there is a real low popping noise coming out of the exhaust.. kind of like a slow bouncing in the rev.. i thought the popping noise is from the plugs missfiring.. because at low boost the car bounces like the plugs aren't firing properly.. could the ISC be the prob with the rev? If that part is having problems it could cause the ecu to burn up? Sorry i don't know to much about stuff like this..
tHanks

 

[TalonTSi-AWD91]

Check the ISC, it's probably causing both problems. http://www.talon-tsi.vze.com/tests.php#ISC

 

[boostedawdtsi]

ok thanks guys, i tried to test the ohms with an ohm meter older than me.. the readings didn't make sense so i will buy a new ohm meter this weekend.... and try it again.

 

[L2RTSiAWD]

Moved to problem diagnosis.

 

[boostedawdtsi]

I checked the isc and according to the ohm meter its only showing like a 1 or -1.. i tried all the ohm sttings and some other readings but none read what its supposed to.. maybe i found the colprit

 

[LightningGSX]

As long as you didn't burn any traces on the PC board, you can just replace that part, and not have to replace the whole ECU. Its a M5269L, they are the same in all 1g ECU's, turbo and NT. Just find a junk ECU, and swap the part.

 

[boostedawdtsi]

Thanks for the info man, i already bought a used ecu and it started to burn up also.. so i need to firgure out what is causing the problem... but that does help out. So i don't have to buy another ecu..