If you did the plug swap thing then you proved out all problems except the reason for not maintaining system rest pressure. For some reason you are not holding system rest pressure. You need to determine what element in the fuel system is letting the pressure down. Refer to D:01:14. There could be a fuel leak, bad check valve on the fuel pump, bad fuel accumulater, or the fuel distributer.Since you said you replaced most of these items the only obvious choices are either leaks or the fuel distributer. I reccomend getting a fuel pressure gauge setup and trying to narrow this down as it is possible in changing some parts one of them may be defective as even new parts can either be bad or go bad. A slight leak at the fuel pump may go unnoticed but it allows the system rest pressure to drop so you cannot tolerate ANY leaks anywhere in the fuel system. Never "tweak" the mixture screw in the metering unit. Once you touch it it can only be properly set on an analyzer and besides that won't solve the problem. Be careful working on fuel injection systems because if you have even a minor leak it can be invisible but the fuel comes out and vaporizes immediatly and if ignited becomes a miniature blowtorch. Fuel injection systems usually operate at high pressures as opposed to the older carbureated systems which only run at about 5 psi. David Teitelbaum vin 10757 --- In dmcnews@xxxx, id <ionicdesign@xxxx> wrote: > i have heard that the gas its self is not flammable it is the gas fumes that are