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Really odd fuel pressure problem!

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Old Sep 6, 2006 | 08:01 PM
  #1  
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QuadCam
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Default Really odd fuel pressure problem!

I normally have about 52 psi of fuel pressure. This is with a walbro 255 and DeatschWerks 550s.

I was playing with my fuel pressure gauge memory recall. I noticed that it was reporting a high psi of 99!!! So, I tried to figure when it got that high because every time I looked at the gauge, it was showing 49-56 psi.

What I discovered was this:

under moderate to high G-force acceleration, my fuel pressure shoots up to at least 99 (highest readout is 99 - digital gauge). If I accelerate in 5th or 6th gear (low Gs), fuel pressure stays around 52. But if I even moderately (1/3 throttle) in 1st gear, I can get the fuel pressure to shoot up.

How can fuel pressure possibly be related to acceleration G forces? I checked many times and it is not a boost related item; I can get the fuel psi to go up beofre I even hit boost in the lower gears.

any insight would be greatly appreciated!!!!

Andrew
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Old Sep 6, 2006 | 08:13 PM
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there is probably a problem with the wiring in your gauge. if your fuel pressure were that high, the A/Fs would go off the chart
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Old Sep 6, 2006 | 08:16 PM
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Originally Posted by phunk
there is probably a problem with the wiring in your gauge. if your fuel pressure were that high, the A/Fs would go off the chart
well........I can only get the car to knock in the high gears. In the lower gears, I can pull through the rpms with any knock. In the high gears (less fuel psi), I get some knock and the UTEC kills the power!
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Old Sep 6, 2006 | 08:20 PM
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does your car have a A/F gauge?
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Old Sep 6, 2006 | 08:22 PM
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yes, I have a UTEC w/ the Tuner Wideband,
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