[91Bullwagon]

thinking about replacing ECU in 91 GL wagon, as CEL has been on and won't spit any codes.

engine is a 3.8L

ECU nos. = F1DF-12A650-HC...

now on the passenger side door frame, and I believe on the unit itself, is the code
S1S2.... which according to ford is the emissions calibration code for the ECU unit.

I'm sure this must matter for some reason, or is the computer "smart" enough to reset these calibrations? I guess the question is, can I just replace the ECU with another F1DF-12650-HC? with any XXXX coded ECU, or must it also include the S1S2 designation?

Of course Ford has no information out there regarding this issue that I can find.

thanx,

Joe

 

[93 sable]

Have you tried disconnecting power from the battery and leaving it disconnected for a while?

 

[91Bullwagon]

yes, been down that road...
the fuel pump seems to keep running once key is on and engine not started, so going to try a box and see....

 

[americanmotorsport.com]

It will trigger the code again. ECU's are either all bad, or all good. Light has to be on for a reason.