Well today I went and started my car and when I turned the key and cranked it there was a loud bang like a slege hammer hitting metal and the car shook a little. Almost sounded like something broke. It didn't start that time but second time it started right up with ease without the bang. Drove it around and she drove perfect like she usually does. No change in oil pressure either. What could that bang have been and how bad is it??

 

My car does this sometimes. Seems to happen more often in cold weather, and only on the first start of the day. I have yet to figure it out. It did this before most of the mods in my sig.

I wonder if something is causing a timing problem on startup? Maybe play in the opti, then when the motor starts up, the PCM corrects for timing?

Not really sure, just wanted to let you know your not alone; and that mine has been doing it for a while with no noticable ill effects.

Thomas.