Fuel pump pressures--87vert
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Fuel pump pressures--87vert
Does anyone know the specs for fuel pressure at the schraeder valve port on the rail???? Assume there is an initial pressure at start-up [2-sec pump run] to prime the injectors then a continuous level once engine has started????? Looked thru the FSM but wasnt clear on the specs [PSI Vs KPa not an issue as my guage has both]?????
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Finally--after months of chasing an engine mis/shutter [700r tranny] while in 3rd or 4th gear at low RPM], I "stumbled" on the problem--low fuel pressure from a failing fuel pump. Once I got the gauge on the fuel rail, pressure was 10 PSI at prime and maybe 20 PSI when/if I got the engine to start [problem was getting worse over time]. New fuel pump went into day and engine now runs great. Funny thing -- the car idled and accelerated pretty well until right at the end when the pump completely failed.
Totally blown-away to find that I could change out the fuel pump thru the fill-cap door opening--I was expecting to have to drop the tank--what a pleasant surprise.
Totally blown-away to find that I could change out the fuel pump thru the fill-cap door opening--I was expecting to have to drop the tank--what a pleasant surprise.
Last edited by dsandmire; Dec 9, 2012 at 01:01 AM.
Safety Car
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From: Melbourne, Victoria, Australia
Fuel pressure can be all over the place between the years, i know my 85 standard only had 30-32 psi with a good pump, i put an adjustable fuel pressure regulator on to set it at 45 psi. The TPI's love 45 psi 
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See my comments on the thread above on "low power/shuttering engine --upon replacing fuel pump, found the fine mesh filter at end of pump had deteriorated, pump probably sucked in the mesh pieces over time and plugged/failed--IMHO....
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From: Anaheim CA
It looked like the pump sock had shredded from rubbing on the bottom of the tank.
