bad fuel pump?

bradass31

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So on my way home today out of no where my fuel pump got very noisy and my car started to sputter. I was able to make it home just taking it easy, if i gave it much gas at all it would cut out and just about die on me. The best way to describe the noise coming from the fuel pump would probably be shaking around some 1" rocks in a beer can I'm almost positive the fuel pump is bad but the car never actually died on me, i let it run at home for another 5 minutes or so and it still never died. Has anyone had this happen to them before? Is there an in-tank fuel pump and an additional in-line pump? Im just not sure why it wouldn't die if the pump was bad- The way it sits now its not drivable, it starts and idles fine, the pump still noisy as hell(rocks in a can sound). Im not sure what to do??? thanks for the help!
the car is an '88 fox with a 5.0 by the way.
 

Liv4Spd

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The best way to describe the noise coming from the fuel pump would probably be shaking around some 1" rocks in a beer can I'm almost positive the fuel pump is bad but the car never actually died on me

That sounds a lot like detonation, which often can be tied to a fuel systems or tuning issues. Though, if that were the case, those sounds would be coming from your engine bay rather than your pump. The pump could be going bad and is just not able to keep up with load under throttle. I'd start doing some exploring (check your plugs, and see if they're indicating lean/rich or maybe see if you can borrow a scanner and see if it's throwing any codes.) I'm by no means a mechanic, and there's a lot of other minds on this board that can add more specific information than I. But the more you can find out and share with the board, the easier it'll be for the folks on here to help diagnose.
 

bradass31

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its definetly not detonation, plugs only have about 1,000 miles on them though it probably wouldn't hurt to check a few. I just replaced the fuel filter also while i was doing my last oil change-
 

4valvemach

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So with the car running and you put your head by the gas tank you hear that sound "rocks in a can" not a buzz/humm from the pump.I had a 89 trans am that would idle fine till you gave it gas then it died I replaced the full pump and it ran great.The same car also made it 15 miles with the bad pump stalling out every time I gave it to much gas.The pump did not make a "rocks in a can" sound just a VERY VERY faint buzz.

DONT FORGET TO CHANGE THE FUEL FILTER AFTER THE PUMP IS PUT IN!!!!!!
 
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Liv4Spd

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Just throwing it out there - but you may consider double checking that your ground isn't loose.
 

bradass31

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The fuel pump has always had a quiet buzz/hum but right before i started having problems (like 30 seconds before) the buzz got VERY loud- and then it went to the "rocks in a bottle" sound. Somthing is definetly plugged up but im pretty sure even if its just a simple plug up that my fuel pump is shot after all this- My plan is to pull the fuel filter and lines just before the fuel rails and try to blow it out with an air compressor:shrug:
Another question i have is will an adjustable fuel pressure regulator give me any more power if i crank the fuel pressure up to 50psi or so? i thought i might go ahead and buy one while im at it and i know a lot of guys use them-
 

blownfox

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Cranking your FP up to 50 will cause your car to be very very rich...I am guessing your car is mostly stock? I dont even think your car would idle right.

If you want more power you could bump the timing or get a short belt. I would fix the car first and then work on the performance.

I ran HCI with 24lbs injector and my FP was at 38 or 39 unplugged and timing at 17 degrees.
 

racewithsnails

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a fuel starvation problem will cause a lean condition which could very well result in detonation so fix your fuel issue before you blow her up
 

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