I'm helping a young friend diagnose his 1999 Pontiac Grand Prix SE no-start condition over the phone. The problem arose gradually with stalling, and hard starting.
We've determined that it has spark and the fuel pump whirs when the key is turned on.
The EVAP vent valve has been replaced because a diagnostic check performed by a local mechanic showed that it was out of range. That didn't do the trick but it gave a minor boost to the economy, as such readings often do.
The same mechanic told him to suspect the MAF.
At this point, the engine will start when one side of the EVAP vent valve is disconnected, I assume it's the side between the valve and the intake, and die when it is reconnected. This tells me that the fuel mixture may be too rich.
One test that I was able to find for a no-start condition involving the MAF was to disconnect the wiring to it and try starting the engine:
[SOLVED] 1999 Grand Prix starts and dies instantly!I will be going to where the car is located soon to see what I can see.
Any advice or tips?
Thanks, Jack