2G Swapped 98 ECU into 97 and received a check engine light.

[Rikolas]

Hey so I recently bought a black box ecu for my tsi awd. It came from a 98 gsx. I swapped it and then received a check engine light . Evap code. Swapped it back to my old ecu, no cel. Could one ecu be bad?

 

[luv2rallye]

Maybe, maybe not. Many Evap tests only happen once every 100 miles. What code is it? An air leaking gas cap can produce P0442.

 

[bduran1220]

I had that problem once then I found out the ecus have nothing to do with it. 98 and 99 have more emission parts then the rest of 97 96 95 that's why when you hook up the 98 black ecu throws a CEL on older DSMs

 

[luv2rallye]

+1 Yes. That may be it. The 98, 99's have an evap emission vent solenoid and fuel tank diff pressure sensor.

 

[Rikolas]

Okay thank you for the responses guys. Sorry it took so long for me to reply, because I just recently ran into another problem with the car. Will do some research and there may possibly be another post here soon.