2002 Oldsmobile Bravada fuel delivery

TRAVIS BURBACH

MEMBER
2002 OLDSMOBILE BRAVADA
6 CYL
AWD
AUTOMATIC
103,000 MILES

My bravada has a mind of its own. The first time trying to start it and it runs fine fuel pressure is 52 psi. As soon as I shut it off the pressure falls to zero and will not refire. Let it sit for 20 minutes and the same story follows. Sometimes it has to sit longer before it will restart and sometimes it will stall before I turn it off and pressure is zero. I just recently had a problem getting it to start at all. Ended up being either the neutral safety or the ignition switch, replaced both of them. I don't know if its related or not but the compressor for the air ride quit working!Your help is greatly appreciated. THANK YOU!

8 Replies

MASTERTECHTIM

MECHANIC
4,749 POSTS

When it wont restart do you have power at th3e gray wire at the fuel pump when cranking? If you do then the fuel pump is no good. *****Number one cause of this is bad connection at fuel pump, if you remove the plug to the fuel pump I bet you will see one terminal burnt and it will be the black wire. Gm has revised the connector when replacing the fuel pump to use thicker gauge wire. This ground connection problem is a symptom that you are de3scribing.

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Thursday, December 4th, 2008 AT 8:35 PM

TRAVIS BURBACH

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8 POSTS

There is no voltage when pressure drops. I removed the fuel tank, no burnt terminals, ground is good, hotwired fuel pump seems to work properly every time voltage is applied. Thanks again for your help anymore ideas?

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Friday, December 5th, 2008 AT 3:31 PM

MASTERTECHTIM

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Ok when you try to start it and it wont start, do you have power at the fuel pump? We need to determine if its a fuel delivery problem or a fuel pump power problem. This pump is powered by a fuel pump relay and it also recieves power from the oil pressure switch

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Saturday, December 6th, 2008 AT 6:07 AM

MASTERTECHTIM

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4,749 POSTS

You say when you turn off truck pressure goes right to zero and it shouldnt drop that fast. That tells me there is a fuel pressure regulator that is not working and thats how your losing your fuel pressure or the fuel pump is no good and not holding the pressure or you have a fuel injector that is leaking but if the fuel injector was leaking then on restart it would be flooded.

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Saturday, December 6th, 2008 AT 6:09 AM

TRAVIS BURBACH

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I started and shut off the truck a few times and the pressure only dropped a few psi. Then I let the truck run for 5 minutes then put it in gear till it died. Pressure was 15 psi and would not restart and pressure went to zero. I took a voltage reading while cranking the starter and it was.3 volts. Also checked the oil pressure sending unit while cranking and voltage was about 8.5. It only seems not to restart after the engine has warmed up. You have been very helpful, tim I appreciate your time on such a confusing problem. Thanks again and hopefully we can solve the problem.