Few problems 90ecu in a 92 starts but...

[amazingsnail]

so im new to the board but not new to the dsm's. I've got a 92tsi awd and a 90 gsx. The 92 was running a few months ago, I purchased it not running tracked down a few problems including a bad ecu, I swapped the 90 ecu into the 92 and surprisingly enough it fired right up idles great but is blowing fuel out the tail pipe, really really rich, tried drivin it the turbo starts spooling (b16g) and it backfires sputters no power etc. and I can smell fuel like crazy. Now im almost positive the 90 ecu shouldnt work with the 92 so is the 90 ecu throwing everything off? i swapped pins 14 and 6 on the ecu harness even though i've heard that doest really work. timings marks are right on, ign timing is on, swapped coils, new plugs and wires etc. any input would be much appreciated! thanks!

 

[cincinnati4g]

Might need to put the 90 igniter chip on the 92, and does swapping the two pins really not work?

 

[amazingsnail]

it *shouldnt* work. the only thing i noticed when i switched the pins is that the car started faster. im not completely sure if it should or shouldn't, i've heard it both ways.

 

[My1GLaser]

Now im almost positive the 90 ecu shouldnt work with the 92 so is the 90 ecu throwing everything off? i swapped pins 14 and 6 on the ecu harness even though i've heard that doest really work.

I am running a 90 Vr4 Ecu in my 92 with pins 6&14 swapped. However, I have DSMLink, so it is using DSM fuel/timing tables and not the VR4 stuff that would have been in the original eprom.

Do you know what the 90 ecu is from, and have you checked the numbers on the eprom? I seem to remember being told that the VR4 tables would make the car run similar to that. The ECU looks the same, its the eprom chip that's different.

 

[amazingsnail]

My1glaszer:
Well the ecu is out of my non running 90 gsx. The part number refers to it being for a fwd not an awd. I haven't opened the case to check to see if its an eprom. The 92 ecu is not. Like I said it will fire right up and idle smooth but throw fuel out the tail pipe like it was free to the public. Withe the coils and transistors being different on the 90 cars I'd expect the wiring and ecu's to be different and don't understand how swapping 2 pins would allow for a 90 ecu to work. The maf was also bad in the 92 so I put my hacked spare in. With the 92 ecu the car surges, sputters etc. So my question is... With the car running soooo rich, no power, backfiring etc when trying to drive it, could that be caused by the 90 ecu?
Cincinnati4g:
Tell me more about swapping the ignitor chip... I'm clueless there

And thanks guys

 

[donniekak]

The only real difference in the coils and ignitor is the tachometer signal. A 90 ecu should work fine in a 91-94 car, as long as 6 and 14 are swapped. Open the case and check for visual damage to the ecu. What injectors are in the car?