fuel issue?? 99 gtp

**jman44** · 12-14-2013

I have a 99 grand prix gtp with 150k miles. I was driving down the road and the car would just shut down. When i tried starting it again it would start then die right away. I was told by multiple ppl it was the fuel pump so i changed it last night, driving home after changing it last night it ran fine for about 15min then as i am driving (50mph) down the road it just died. Tried starting it and it starts then dies right away. My next guess is bad relay or brain box? Any ideas any help would be awesome.

**jman44** · 12-14-2013

btw it has a brand new fuel filter

**CapnBreakAlot** · 12-14-2013

Did you try bending the relay tab to set the pump in high speed mode? Just an idea.

**jman44** · 12-14-2013

could these issues be caused by a bad relay? but no i havent

**CapnBreakAlot** · 12-14-2013

Try this first. It's worth a shot.

**Scottydoggs** · 12-14-2013

sounds like a crank sensor really, the bypass trick is if it dont start up.

did the tach drop to zero before it stalled? if so its the crank sensor.

**CapnBreakAlot** · 12-14-2013

You would know better than I would Scotty. I just thought I'd take a shot in the dark and suggest it haha.

**jman44** · 12-14-2013

yes it did drop to zero but wouldnt my car throw codes on the dash? i have no codes on my dash but is that the problem?? like you said it does hit zero before completely dying

**Scottydoggs** · 12-14-2013

you need a crank sensor for sure.

and no, this sensor sadly hardly ever set the cel on the dash, why idk. but it should lol

the how to. http://www.grandprixforums.net/showt...e+crank+sensor

**jman44** · 12-14-2013

thanks alot!!!! and yeah that is dumb it should throw codes

**02NavyBlue** · 12-14-2013

Obviously the tach goes to 0 when it shuts off...because it's no longer running. What he meant is does it go to 0 about a second before it shuts off? You may have understood that, I'm not sure but just wanted to clarify. I'd hate for you to replace it and still have the issue or something.

**jman44** · 12-20-2013

Replaced crank sen an still will start then die it. It is doing the same thing as before except now it dont hit zero then die it jus dies. So far has new fuel pump new crank sens and new fuel filtrt help please i am totally lost

**ericspecullaas** · 12-20-2013

did you hack the wires when you changed your fuel pump? when I just replaced mine I didnt hack the wires. It could be that the a connection is not good enough to let the pump run it could be randomly connecting and disconnecting allowing it run then turn off. but thats just my 0.02

**jman44** · 12-20-2013

They are all connected good i dont think the pump was bad

**Scottydoggs** · 12-20-2013

will it drive? then stall? or start then stall?

if its start then stall, try the resistor bypass like posted by the captain up there.

**jman44** · 12-20-2013

What is the res bypass? And start stall

**Scottydoggs** · 12-20-2013

you turn the key it starts, then less then 5 seconds it stalls.

if you bend this tab out on the relay as posted here, its should stay running, this puts the pump in high speed mode full time. if the resistor is bad this makes it works, and tell you the resistor is bad.