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Re: An Automotive Question

Posted: Fri Jul 14, 2023 11:40 am
by teetoppz28
audiophile wrote:
Fri Jul 14, 2023 11:28 am
teetoppz28 wrote:
Thu Jul 13, 2023 9:52 am
My '06 GTO with the LS2 had the Deceleration Fuel Cut-Off (DFCO) and with my aftermarket race exhaust, every time I'd press the clutch in, DFCO would kick in, causing pops and crackles, kinda resembling back-firing. Did get a bit annoying, especially late nights when driving through my neighborhood. That exhaust was amazing, I loved always setting off my coworkers' car alarms in the parking garage! 8)
If it was cut off the fuel, not sure why it would crack or pop.

No fuel, no pop.

Are you sure it wasn't spark cutoff?
It's been many years since I've owned that car, but if I recall, it was related to the DFCO causing a lean condition misfire. I could be wrong on that, however.

Re: An Automotive Question

Posted: Sat Jul 15, 2023 12:14 am
by Motown322
it's unburnt fuel getting into the exhaust and igniting there as opposed to getting fired off by the spark plugs in the cylinder.

Re: An Automotive Question

Posted: Sat Jul 15, 2023 1:59 pm
by audiophile
A lean misfire could cause crackles if the DFCO tapered the fuel delivery slowly and it found a red-hot surface to ignite in (convertor).

Spark cutoff it would be lot more likely to happen!