I have an OBD1 chipped ECU for my 97 GSR swap in my 94 teggy...How could you tell if an ECU is faulty? Cuz ive gone through two different motors using the same ECU, and the ECU keeps throwing the same one CEL code both times in the two different motors ive had in the car. any thoughts?!

 

the only way to check is by plugging it into some one else's car..... have you tried pullling the codes? if there are codes to pull, then its the motor/sensors. If its a solid cel, then the chip is bad or the ecu can be bad.

 

yah ive pulled the codes, theres just only one, which is code 7, and that same code appeared on the motor before as well. What do you mean by solid CEL?

 

Code 7 is for the throttle position sensor (TPS). I'm guessing you're using the same TPS from the old motor? If so, then that is why the code persists. See about getting the sensor diagnosed. I voltage check should tell you if it's within specs, but I don't know the values off the top of my head. It could also be a wiring issue since you have gone OBD2-OBD1. If you can swap your ecu into a friends B18C1 equipped car, or their ecu into yours, you should be able to determine if the problem is in the ECU or not.

A solid CEL - check engine light - means that when you jump the diagnostic connector, the light stays lit instead of blinking codes.

 

Correct..TPS sensor, the motor before was my LS/VTEC had the OBD1 B16A IM and TB, and the motor now i have is obd2 IM and TB on my gsr. Still the same code, but yah it pulsates when i jump the plug with a paperclip. Could it possibly be a bad ecu? or just coincidently have another faulty/bad TPS sensor. ? Unfortunately none of my friends have a GSR but me..everyone is either d series, ls/v's, b20v's, stock ls, b16, or boosted..lol

 

Well it could possibly be a few things. There may be a problem in the wiring, or in the OBD jumper harness (assuming you have one) connections, pins... The service manual diagnostic procedure should tell you if the ECU is bad or not. Don't suppose you have a service manual? If not you can gain access to it online for reasonbly cheap.

If your friend w/the b16 is running an OEM OBD1 ECU, then you can plug that in and at least know if there is an actual TPS problem.

 

ill go ahead and look into it...thanks!