Mechanics

CHEVY LOW FUEL PRESSURE

1998 Chevrolet Blazer

1998 Chevy Blazer 6 cyl Four Wheel Drive Automatic

I have a problem with my fuel system we have replaced my fuel pump, fuel rail, fuel filter, spark plugs, rotor and distributer cap, wires, map sensor, and the spider, and my fuel pressure is 25 psi and it still wont start we can put gas in the carb and it will stay running but as soon as you shut it off for a long period of time or overnight it will not start again on its own and we scaned it several times and no trouble codes could anyone give me any suggestions could someone pleaseeee help me thank you in advance dee
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Everdee69
September 12, 2008.



You do not have a carb. It is a throttle body -- very different. Your fuel pressure should be between 55 and 60 PSI. If you have the injector unit that looks like a spider then you do not have a fuel rail. What fuel rail are you talking about? When you changed the spider unit did you put a new fuel pressure regulator in? Make sure the new fuel filter is installed properly. The fuel filter is directional, it's easy to make this mistake. Did you install the correct fuel pump?

Tiny
Pear69
Sep 12, 2008.
Your right I do not have a carb, and I do not have a fuel rail I have the spider and the garage next door said the fuel pressure regulator was changed when they changed the spider, as for the fuel pump they changed so I can only assume it is installed correctly, and as for the fuel filter I was there when they put it in and the one for my truck only goes one way one end clips the other screws on it looked exactly like the one they took off. And that had a lot of black gunk coming out. Any suggestions? Dee

Tiny
Everdee69
Sep 12, 2008.
Your fuel pressure should be 55 to 60 psi. There is something blocking the fuel supply line, or the line is sucking air somewhere. When the fuel pump was changed, the tank had to be dropped and drained. Was the fuel tank cleaned at this point? The black gunk that came out of the fuel filter was probably the reason the fuel pump failed. Eventhough it's a new fuel filter, take it out and see if there is any black gunk in it. If so then you should drop the tank and clean it out.
A fuel line may also be pinched. The lines that connect to the fuel pump sending unit are flexible. They may have inadvertantly gotten pinched or something like that.
If all of that fails then the only thing left is the fuel pump. It is not unheared of to get a bad (new) pump. Let me know what you find.

Tiny
Pear69
Sep 14, 2008.