OK heres the problem if I bring the RPMs up from idle and hold it at around 3000 the fuel pressure jumps about 5psi higher then drops it doesnt raise the full 10psi and hold.I disconnected the vaccum line to the regulator and the pressure raised and held at46psi.The fuel pump is getting 13.3 volts all the time. The regulator is only 7 months old and the fuel pump is about a year and a half old.What else should I check or should I just buy a new fuel pump?

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89 350 TPI,comp cam,edelbrock intake base,SLP headers,highflo cats,flomaster cat back,accel 300+ ign,ported plenum and runners,ported maf,auto w/shiftkit,cold air induction,AFPR,Ed wright chip,3.23 posie best ET 14.011@98.72mph without cam/New best 13.926@98.27mph

 

E-man,

You've already proven that the pump can maintain pressure of 46 PSIG or better, and you've proven that there are no circuit interruptions to the pump. What you are describing sounds like a FLOW problem, not a PRESSURE problem. As long as the pump can maintain pressure but is not able to deliver an adequate volume of fuel under heavy demand, I'd check the lines for kinks and bends and replace the filter.

Usually, a pump that won't make pressure won't get better by itself. A filter that will only pass a little fuel might operate on an idleing or lightly loaded engine, but can starve the system at heavy loads. Sound familiar?

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Later,
Vader
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I hope your right it was a real pain in @$$ getting the gas tank out.thanks

 

I changed the fuel filter it was not the problem.So I was just sitting there looking stumped and said let me put the stock fuel regulator back on problem solved!I will never buy another adjustable regulator again this is the second one to fail on me first was a crain the screw striped now it was a holley for whatever reason failed.

 

E-Man,

You may have had some debris in the valve seat on the FPR, or a soft (inferior) valve disc.

I've never had a problem with my AFPR, but I only paid about 50¢ for mine:

AFPR.pdf

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Later,
Vader
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"Click - Click - BOOM!"
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