2004 grand prix stalling

pontiac
grandprix

#1

I have a 2004 grand prix 3.8 engine that keeps stalling. I notice it happens mostly when speed up and go up hill. I changed the crankshaft sensor and cleaned the throttle body. But didn’t help. There’s no check engine light on. Any ideas on what it can be? Thanks.


#2

Also did a fuel pressure test and it was fine.


#3

Good fuel pressure does not necessarily equal good flow. What’s the fuel pressure when the problem’s occurring? Check for plugged cat. My specs say “less than 1 psi @ 2000 RPM in park”.