So it's official.

[georgio440]

My ECU has reflashed itself back to the stock tune. I installed my Xcal 3 last week, and everything was fine. A week later my CEL came back on again and the car is running exactly how it was prior to my mail-order tune from American Muscle. It's running rich, backfiring a ton, my fuel economy is horrible, and just not running as well. I'm just going to upload the stock tune, then upload the mail order tune and see what happens. Has anyone else experienced this? Any advice would be great. Thanks.

 

[nyuk98gt]

geogio440:

No flame intended but your PCM cannot flash itself back to stock. When the PCM is flashed, the keep alive memory (KAM) is cleared (in '98 and later models) so all of the learned fuel corrections and other learned corrections are lost. It is most likely that clearing the KAM is what made your engine run better but now that the PCM has learned the corrections that it did before the flash the engine is running less than ideal. If you are getting a CEL then a new tune is probably not going to fix a hardware problem. (AM is a good tuner from what I have read by other posters, btw). What is the DTC (stored code)? Please post it up along with your mods and let's go from there.

Chris

***edit: OK, saw your sig (sorry I missed it the first time through, lol). ***end of edit

 

[2000fordstanggt]

have you changed your plugs recently?

 

[georgio440]

Yeah, the plugs are a few months old. I'll get the code for you when the CEL pops up again. I just put it back to the stock tune and back to the mail-order tune. We'll see what happens.