Anyone know why my fuel pressure is low and goes to zero the instant the engine is shut off? It''s at about 32 at idle. Injectors are fine. Is it the fuel filter/regulator or is it the fuel pump? Or can you tell? Where can I get a gauge that will mate with Saturn fuel lines?


Thanks.

 

Well, for a 99 model,32 psiis definitely low. Pressure for that year should run between 40 and 55 psi at idle. I got my gage through AutoZone, and the fitting came as part of the package. Mine attaches to the fuel rail.


With the engine running at idle, pinch the fuel return line shut, and watch the gage. If the pressure does not rise either the fuel pump is defective or you have a blockage in the fuel feed line. If the pressure rises sharply when you pinch the return line, the pressure regulator is bad, and should be replaced.

 

What year is the car? Its possible for the requlator to go bad. I''ve seen it happen.

There is a test port to check fuel pressure on the fuel line a few inches before the fuel rail.

 

Mike -


I am assuming that it is a 1999 SL2, because that is what the header on the page says ...

 

Ahhh crap. Missed that.

1999 was a transition year. What intake manifold does the engine have? Aluminum with a horizontally facing throttle body or plastic with the throttle body facing straight up?Edited by: Low Saturn

 

Thanks. A fuel gauge kit from AutoZone costs about $50. At that price I could almost have a fuel filter/regulator, though I guess that it''d be a nice tool to have anyway.

 

Has an aluminum throttle body. I am hesitant to pinch the fuel lines, as the ones under the car are plastic, and are labeled "Do not pinch."

 

Then the fuel pressure test port is on the fuel line a few inches from the fuel rail.

 

Yeah. I tested pressure there. It''s about 32 with the engine running, and drops to 0 right away when the engine is shut off. There''s another test port under the car. I''ll give it all a look once the weather improves, or I become brave and clothed enough to endure the cold. Seems that Autozone actually sells a gauge for only $25. I don''t know if it comes with appropriate fittings. I''ll have to investigate.


Thanks for the help.


T.

 

The hose from the pressure tester comes in realy handy when having to empty the tank on a parts cars a s well.