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2000 grand prix fuel pump relay not activating

bookrat

New member
I have a 2000 grand prix 3.8 non supercharged and while driving it my engine just died. Once I got it home I found that when I turned the key that I did not hear the fuel pump priming. I found that I was getting 12v to the fuel pump fuse and that the fuse is good allowing the 12v to pass through to the relay contact. I then bypassed the relay and found that I could then hear the fuel pump prime. I checked the relay coil and one side I am getting a solid ground connection and the other side I am getting 4.5v when the key is turned. I picked up several of the relays at the local junk yard and after trying them all I finally bent the coil pin on one of the relays so I could apply voltage directly and see if the relay activates. When I put a 12v on the bent pin I heard the relay click and heard the pump prime. I did try to have another person crank the engine while I was manually activating the relay but I didn't have any luck. In my Haynes book it looks like the signal to activate the relay comes from the computer. I could not find listed anywhere what voltage I should be getting from the computer to turn on the relay. Any suggestions would be greatly appreciated:confused:
 


Not sure what year this switched, but at least 97-98 have two relays and a resister for the dual stage venturi pumps, but I don't think 2000 had those.

What I'd look for is a constant voltage from 2-12 volts to the relay on pin, and a good ground on the other side.

Could be a fuel pump resister. Use this video: 97 Grand Prix GTP starts up then dies. How to check fuel pump resistor - YouTube

And use this link to fix: Rocky Mountain Club Grand Prix

If it isn't that, let me know, I've got the full diagram with the second speed control relay.

Oh yeah, and let me know if your car doesn't have the second relay or resister. Good luck!
 
My year only has one relay and does not have the relay for the switched resistor. I was looking on the Racetronix site and guess i'm not familiar with the site since I didn't see the wiring harness for my vehicle.
 
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