Mechanics

CHEVY FUEL PUMP

2000 Chevrolet S-10

2000 Chevy S-10 6 cyl Four Wheel Drive Automatic 98000 miles

My 2000 S-10 ZR2 has a fuel delivery problem. It will run fine for about 40 minutes then it seems to stave for fuel when accelerating. I replaced the fuel pump and it runs a lot better but continues to act up after about 40 minutes of driving. If I pull of the road and key the truck a few times it's good to go for a little while, but about 30 minutes later it acts up again. I don't know what it is please advise.
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Adamball
March 12, 2008.




Is or has the check engine light come on? If so have it scanned at Autozone (they do it free) and get back with the codesMight be the cat converter. Try loosening the exhaust before the cat and see if it will run better. As far as fuel goes, you will need a manual gauge set up for a road test to see if that is the problem

Tiny
Jack42
Mar 12, 2008.
It pulled an O2 sensor code, so I replaced them, it still acting up and not sending any codes.

Tiny
Adamball
Mar 12, 2008.
You not only want to know the fuel pressure, but that the pressure is holding.

When I close the return line it should jump but it doesnt, the fuel pressure is good so I dont know.

Tiny
Adamball
Mar 14, 2008.
Like Jack said, the gauge needs to be hooked up, run out to the windsheild and monitored when the problem happens.

Some pressure does not mean goo pressure. IIt MUST be in spec. Even when the problem is happening.

So Hooked up the the gauge and it reads about 45 to 50 psi even when acting up. I hard wired the pump to the battery to see if it was the wiring and it still does it about 30 minutes in. The pressure seems fine but its not getting volume, if that makes any sense. I have replaced the relay many times and it will run fine for about 40 mins but then it acts up again only when getting on the throttle. I replace the wiring harnes for the pump, the fuel filter, the actual pump and the fuel pressure regulator. I think maybe I need a factory pump. Could the aftermarket pump be getting hot and acting up. I just hate to replace the pump again, the one in it is like 3 weeks old, but I think its still under warrenty but I am not sure. Any suggestions

Tiny
Adamball
Mar 15, 2008.
Yes the poor volume makes a lot of sense. We have had too many problems with many aftermarket pumps. You can buy delco and dephi pumps aftermarket. Those are the only ones we use on GMs to offer any kind of labor warranty. We don't like replacing them for free either.

The spec on the fuel pump is 55-61. I have found that even a couple pounds out of spec will cause problems.

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Ok I took out the pump I replaced about 4 weeks ago and I found a lot of fine dirt particals in the fuel. I think the were getting past the sock, also the pump was stained like brownish a little bit. I think this could have been the main problem. I cleanded out the tank very well and replaced the pump with an original GM part. This should work. How would dirt get into the fuel tank and what can I do to prevent it from happening again. Thank you.

Tiny
Adamball
Mar 20, 2008.
Tough to do as it comes in from the filling station tanks. You can rinse out the tank with fresh gas or replace the tank if it's that bad.

The filter should always be replaced at the same time as the pump.

The pump should be under warranty since it is not giving the right pressure spec.


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