Fuel pump pressure test?
#1
Black and blue
Thread Starter
Fuel pump pressure test?
95/f150 /5.0 (running lean on right side is original problem)
just did pressure test.20 psi engine on,35-37 psi at idle.
New pump? If so whole unit or just pump?
Also, replaced fuel filter week before test
Let me know what you think
Thanks
just did pressure test.20 psi engine on,35-37 psi at idle.
New pump? If so whole unit or just pump?
Also, replaced fuel filter week before test
Let me know what you think
Thanks
#2
has left the building
What about the pressure regulator?
#3
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Join Date: Jan 2018
Location: Memphis, TN, Earth, Milky Way
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I think: not enough info (too short sentences) more details needed.
#4
Senior Member
Are you having a problem? Specs call for 30-45 psi at idle.You can go one step further, pull the vacuum line off the regulator and start the engine. Pressure should go up and be fairly steady when you work the throttle. If you have a brief large drop in pressure before the pressure builds back up, the pump is weak. Do not change the regulator unless raw fuel comes out of the vacuum port of the regulator.I don't think that is the case as the engine would be running poorly and extremely rich.
Last edited by raski; 10-01-2020 at 05:50 AM.
#5
Senior Member
Just happened to me in the past two weeks problem lean condition . My 95 5.0 only has one o2 sensor so lean condition is not related to a side of engine . Your fuel pressure should jump up with vacuum hose disconnected or when you wide open throttle . I have two different gauges and they read different . After all the testing I did I had to clean MAF and all is well . No code for MAF but to clean it I had to remove the plate protecting the elements to clean it properly .Codes and tests are important before throwing parts at it ..
#6
Black and blue
Thread Starter
Just found ?
Thank you for your info on checking the pressure regulator,
just found small air leak in vac line to regulator, maybe the problem?what do you think?
Will replace and let you know if check light goes out
Thanks again
just found small air leak in vac line to regulator, maybe the problem?what do you think?
Will replace and let you know if check light goes out
Thanks again