Thread: Smoke upon (cold) hard acceleration...

Sure..

Being supercharged your engine is being force fed air via the charger. The programming in the pcm is looking at the boost pressure and fueling accordingly. However since our cars are shipped all over the world to many climates etc. they are generally programmed. Then there's other systems put in place to try and ensure that if low octane fuel, high humidy, hot temps, odd stuff is present that they engine should run and run decently w/o blowing up. This is where hte knock sensors come in. They measure the amount of noise in the engine block. When the level hits a certain amount or noise happens when the pcm doesn't expect it.. the pcm has the programming to retard the timing. This takes away power and helps stop the dectonation issue from happening. This is also part of the system that tells us which cylinder is misfiring. Pretty cool that a sensor can hear and the pcm can interpret which cylinder an issue is happening on.