Can fuel pressure affect idle?

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Apr 27, 2009 | 06:58 PM

formula1785

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Staging Lane

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From: Bakersfield,CA

Can fuel pressure affect idle?

at cold start idle is sometimes normal but sometimes bout a thousand..when its warmed up on the second start up its bout normal..now i know that i have long cranking to start..cuz my fuel pump is going south...just wanted to know can fuel pressure affect idle??thanks

Apr 27, 2009 | 07:09 PM

ss.slp.ls1

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From: Orange County, CA

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Originally Posted by formula1785

Low fuel pressure can cause hard starts, but you'd also notice stumbling while accelerating under load. How do you know your fuel pump is going south? I'd get a fuel pressure gauge and see what your pressure is doing at idle and WOT under load.

Apr 28, 2009 | 07:24 AM

LM97Z

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Quote:

Originally Posted by formula1785

If you know your FP is going out, i wouldn't second guess anything, change it along with a fresh filter, i would say if the pressure isn't too low, NO it won't affect idle too much because the PCM will sometimes currect this if conditions aren't too out of wack, but it can/will affect start ups like hard starting, especially if it doesn't prime properly or not at all, you'll know this when you turn the key on, you don't hear that "Buzz" sound, i had a weak pump in mine, it idle'd good, didn't stumble, even under WOT it wasn't bad, but it was a bitch to start because it wouldn't prime, but after it was running the pressure was around 35 lbs., about 10 lbs. lower then it should be, so if you know the pump is going out, just change it.

Apr 28, 2009 | 02:51 PM

formula1785

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Staging Lane

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From: Bakersfield,CA

well i cycle the key to get it started faster.and it does stumble at cold start with the first drive but after its been warm and on the second start up its fine like the pressure is changed after it warms up..only problem for me right now in changing it is...i got a free fuel pump but! but my sending unit is all wacked out and if im going to change the fuel pump then i should change the sending unit with all that work you know.yea and a dealer part is a ton!

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