Symptoms of a failing fuel pump?
09-09-2009, 07:47 AM
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Symptoms of a failing fuel pump? Do they go all at once or just start to loose fuel pressure. If the latter, when did you notice a change?
When cruising at 70 my fuel pressure dropped from 61 to 54. It recovered to 61 when I decreased speed to 55. Never did that before.
When cruising at 70 my fuel pressure dropped from 61 to 54. It recovered to 61 when I decreased speed to 55. Never did that before.
09-09-2009, 05:59 PM
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I think what you are seeing is normal my fuel pressure fluctuates a little bit while I'm driving. Are you using a mechanical gauge on the end of the fuel rail? But to answer your question a fuel pump that is failing would have some of the following.
Hesitation / bogging
Loss of power
Misfire
Hesitation / bogging
Loss of power
Misfire
09-10-2009, 08:38 AM
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It is a SPA digital gauge. I just never saw that happen before. Usually my fuel pressure fluctuates between 59-62.5. It went down to 54 and stayed there. So that is a 5 psi drop.
09-10-2009, 11:04 AM
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you could be seeing the pressure fluctuate because of voltage at the pump. but I don't think you have a failing pump. How many miles are on the pump and when was the last time the fuel filter was changed? Are you running any kind of forced induction?
09-10-2009, 03:08 PM
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it varies i had 3 that just quit and a few that vary pressure most likely you see varied A/F
for example it it ran 12.5 and now in the SAME (dyno/ tune) situations its goin up and down then its failing
for example it it ran 12.5 and now in the SAME (dyno/ tune) situations its goin up and down then its failing
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09-13-2009, 05:14 PM
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KB BAP with 3 psi Hobbs switch.
36K miles, fuel filter changed about 15K miles ago.
No hesitation noted.
I am thinking it might be the Fuel gauge sending unit.
I am thinking it might be the Fuel gauge sending unit.
