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Hard Starting Due To Loss Of Fuel Pressure - Help!

brufener

By brufener
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rs250 Enthusiast

rs250

Posted
Posted

Well no real need to change the fuse I guess, the original 20 amp one is in there and the truck fires right up as normal with the new pump...quiet as can be!!

 

Pulling the bed to replace the pump HAS to be the easiest way, very simple job!! So, at least in my case a hard start and low pressure must have been a faulty check valve in the pump!

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RayRayGSXR
RayRayGSXR

I too have the same problem, I have 2002 Yukon, and it started off... if it was left with under a 1/4 tank of gas and sat over night it wouldn't start. I noticed it progressively getting worse that if

Leonidas Ureña Echeverr&#23 New Member

Leonidas Ureña Echeverr&#23

Posted
Posted (edited)

Hello,

 

I have a 2001 suburban V8 5.3, engine hesitates a lot, dies on me on the road, starts back up but very weak. We just did a tune up and fuel filter change thinking that could be the issue but it actually got worse. I checked the fuel pressure and it is 20psi with the ignition on and 23 psi with the car running. I changed the fuel pressure regulator and the fuel pressure regulator vacuum hose (which has been discontinued by gm awful move), the problem still happens and the pressure is still the same.. There is no gas smell anywhere other than when the engine starts and it is hesitating, no black smoke. The only hose that I know it has a leak is the fuel intake hose from the gas cap to the gas tank... would that make the pressure drop that low? any ideas what could be causing the problem?

Edited by Leonidas Ureña Echeverrí a
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CS8804 New Member

CS8804

Posted
Posted

I have a 03 GMC Sierra and have a slow drop in pressure as well. 55 psi to 20 in about 20 min. I too have to turn the key twice to get it to prime. Thought it was okay since it’s a theft deterrent but now I just want to fix it. I found that I had a leaky injector, so fixed that and hooked up gauge and it now more slowly drops psi but still drops. I replaced pump and did that splice connector thing and it still drops. Changed fuel filter and old one had a bunch of black stuff in it. I also changed the fpr. I think the fuel pump still might be the problem. I also get get a code of P0446z I read from another thread that the pressure sensor in the fuel pump was giving that code. The thread also stated the guy replaced pump again with a different one and all his problems were gone.  I tested the fuel pump directly and it gave me a really high pressure over 60 psi then slowly dropped but the gauge connection was leaking. I’m at wits end to figure this one out. 

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