From day of the install my 06 APS M6 vert, APS full 3" exhaust has had a nasty backfire on decel. At times it was as loud as a gun shot! The tuner has been very patient trying to tune it out. The decel fuel trim adjustments did not help. Last night he turned off the decel fuel trim, and the back firing is gone. Left is nice burbble, just the way it should be. My only concern is will it do any harm to the pistons (stock lower end, not forged). I know running lean with forced induction can cause big problems. Everything else seems fine, it accelerates exactly the same. Any feedback is appreciated.

Thanks,

Rick V

 

No. I tried adjusting the DFCO and never got it to work right. It just backfired, as you experienced. So I left it stock. That's what your tuner really meant. As far as I can determine, it's just reducing the fuel during decelleration, why you can't turn it off is kind of stupid to me, so there are other adjustments ie minimal injector in put which seem to run all the time. It won't hurt your motor backfiring, just sounds stupid and bad. I have yet to see a DFCO setting that works. You might want to try HPTuners.com or search the other tuner boards.