EBstreetbully

Hello everyone. ONLY during warm up this happens and not everytime. I'd say about 2 out of 5 times it will come on and flashes anywhere from 5 seconds to 20 seconds. Car pulls hard and strong with no hiccups and was tuned at LG motorsports in Texas. Does have a small cam (unknown specs). Someone said that a check engine light flashing was due to misfire, but why would it ONLY happen during warm up? Any thoughts would be greatly appreciated! Thanks..

The Alchemist

iTrader: (19)

Simple. During warmup, the fuel being injected into the cylinder isn't fully atomized due to the lack of heat, in addition, the rings and cylinder may not be sealing completely, which is totally normal since all metals expand as they get warm. So tolerances have to be accounted for when even a factory motor is being built.

Now, add to the equation that you have a larger than stock cam, which causes a slight loss in low rpm efficiency and you get more random misfires when cold than the pcm is expecting to see.

You can either chose to ignore it, or go into the tune and raise the threshold for random misfire detection.