Sould fuel pressure gauge be dithering rapidly?
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I recently purchased an analog fuel pressure gauge with the correct size fitting that screws right onto the end of the fuel rail. I just put an adjustable FPR on and when the car is idling or revved the fuel pressure dithers rapidly between a 10 psi swing. The needle moves so fast it is a blur. Is this how it should be or should it stay right on a specific pressure? I am not 100% sure if it did the same with the 3 bar fpr that was on there before but I will probably put the 3 bar back on to see if it dithers rapidly as well.
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I have the stock pump and stock injectors. When I look on youtube for fuel pressure tests every one I see the needle does not rapidly dither all over the place. It just stays at what ever the pressure is. Can someone else confirm that the gauge should dither? If it is supposed to dither then does that mean the highest of the swing for a 3 bar fpr should be 43 pounds even though it rapidly dithers back and forth from 33 to 43?
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BTW, not saying it "should" jump around, just that it's common with typical cheap-o gauges... I think the mid-point is probably the best bet...
See references to it in these threads....
https://rennlist.com/forums/944-turb...ng-normal.html
https://rennlist.com/forums/924-931-...ail-broke.html
See references to it in these threads....
https://rennlist.com/forums/944-turb...ng-normal.html
https://rennlist.com/forums/924-931-...ail-broke.html
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My Autometer gauge from LR doesn't move at all. It is rock solid at 43psi no matter what RPM and I'm running 80# injectors with the Bosch HV fuel pump.
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I was going to suggest the damper as well.
My gauge, which I have not installed yet, is fluid filled but also has some sort of adjustment screw at the fitting on the back of the gauge, which if I remember correctly is for dampening. Sort of like a needle valve. It's at my Dad's place, so I can't look right now.
My gauge, which I have not installed yet, is fluid filled but also has some sort of adjustment screw at the fitting on the back of the gauge, which if I remember correctly is for dampening. Sort of like a needle valve. It's at my Dad's place, so I can't look right now.