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Lately i've been having problems with my car missing. I used a pressure gauge at the fuel regulator and only got 30 psi with the vacuum on and off. could this be the fuel pump or the regulator.
 

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I would argue that it could be the fuel pump also if it only goes to 30 psi.

If the pump is only making 30, the regulator can't control the pressure because ,vacuum line on or off, the regulator is closed trying to build pressure higher than the pump can deliver.

If the return line is pulled off the regulator and a hose on it is put in a bucket, fuel flowing out of the hose at 30 psi says the regulator.
If no fuel is coming out of the hose at 30 psi, look at filter, pump, pump to sender internal hose
 

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You can also wrap return line with rag and GENTLY squeeze it with vice grip. A plastic tipped squeeze type clamp tool works best.
If the pressure doesn't increase check filter & pump.
If the pressure does increase replace the regulator.
 

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Sorry, I would never "pinch off " a nylon fuel line,
A new one, you will put stress lines in it .
An 20 plus year old hardened one, pretty much certain to damage it.
Ah...my bad I thought they had a section of rubber @ fuel rail.
Yeah, I wouldn't squeeze nylon.
 

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I would argue that it could be the fuel pump also if it only goes to 30 psi.

If the pump is only making 30, the regulator can't control the pressure because ,vacuum line on or off, the regulator is closed trying to build pressure higher than the pump can deliver.

If the return line is pulled off the regulator and a hose on it is put in a bucket, fuel flowing out of the hose at 30 psi says the regulator.
If no fuel is coming out of the hose at 30 psi, look at filter, pump, pump to sender internal hose
I totally agree. I had 30 psi and long cranks. Exactly the same symptoms including no pressure change with vacuum off the FPR. Replaced the (failing) fuel pump and everything was back to normal.
The original wiring was a bit fried, so six months later I have intermittent no start condition. Will have to put new fuel pump/sending unit assembly. Arghhhhh!
 

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Discussion Starter #8
changed fuel pump and all is well.
 
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