This car has not been in any accidents. I pulled the valve off of the top of the charcoal evap canister. I have a lot of tools including a motorized vacuum pump. I pulled a vacuum on the valve when energized (it's normally open) and it held up to 16 inches of vacuum. I had read that the CVS valve was often the problem. I assumed that this was the valve I had tested, so even though I thought it was good, I replaced it anyway. The light stayed off for 2 days, but came back on today. I also pulled a vacuum on the charcoal canister, check the valve that allows the vacuum to go from the intake to the canister. Did a vacuum check on the lines going to the the canister, they are fine. I really need the troubling shooting proceedure for this system. I ordered the Helm's repair manual for $85 bucks, but this will take 10 days to get. Anyone have the trouble shooting proceedure?? Thanks