Mechanics

FUEL PUMP

2002 Oldsmobile Bravada • 114,000 miles

Car will crank and start if I use starting spray but I am not getting any power to the fuel pump. Replaced the pump and it still won't get power to it. Also the fuel pump relay sounds like its kicking our and not letting the power go back to the fuel pump. I am stumped at this point what's the problem and how do I fix it? Also would it be safe to bypass the relay and run my own power from the batt. Using a fuse and toggle switch or would that destroy the truck
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Jeremy896
September 15, 2013.



Check to see if poer is going to an d from relay, switch relays with a like relay and see if it works. Then check the gray wire going to fuel pump it ma be shorting out. You shouldn't bypass the pump for safety reasons.


Hmac300
Sep 15, 2013.
Ok I won't bypass the relay but I did change it with one of the same kind and that one kicks out also. I do have power going to the relay but it kicks off so that there's no power going to the pump


Tiny
Jeremy896
Sep 15, 2013.
Then the relay isn't making contact in the fuse box or the wire is shorted on the frame someplace I would try to back track the wire and see if it's shorted out or check from the fuse box. Also check the ground for the relay it's on the rh side of rear head.


Hmac300
Sep 15, 2013.
Ok I will do that soon as I get home. I was also told that the pass lock system could be preventing the fuel system to work is this also true and if so how do I reset the pass lock system because the truck was fine until I changed the valve cover gasket. I think moving all those wires may have done something because it ran until I cut it off and it hasn't started since.


Tiny
Jeremy896
Sep 15, 2013.
See pic for reset it's pretty easy.


Hmac300
Sep 15, 2013.
Hey that seems to have worked, the truck is now running but it's missing really bad check engine light is on. It stays steady for a minute and then it flashes for a few then goes back to steady. Could I have messed up a sensor by using that starting fluid? I put in 6 new plugs and the miss is still there. I've also made sure everything is plugged in properly thanks for your assistance you've saved me a lot of money and time.


Tiny
Jeremy896
Sep 16, 2013.
Scan for codes and check fuelpressure with a guage auto parts scan for free if it's ap0300 that is a misfire and are very hard to diagnose. So have a pro do it.


Hmac300
Sep 16, 2013.
Thank you again, had it scanned and its a misfire in the number one cylinder, I pulled the plug and its oil filled the others are dry if I can't find a non fouling plug it's time to take it to the shop as you've said. Wonder why it's wet?


Tiny
Jeremy896
Sep 16, 2013.
Cold be a few things, a valve seal, low compression an injector leaking, or a piston/ring problem.


Hmac300
Sep 16, 2013.