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fuel pressure drops

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Old 08-27-2008, 04:14 PM   #1
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Default fuel pressure drops

i was taking my car on a trip last weekend and was cruising and my fuel pressure gauge started jumping all over the place like 50 40 20 40. well i came up on stoped traffic and the car stalled, it started and got me off the highway. after letting it sit for a little the pressure came back up to 58 but would start to fall off a lil if i reved it, so i had it towed home on a flat bed. so it wouldnt strand me somewere else. anyway when i got home i took it down the road and under wot the pressure just starts dropping fast. Is this a bad pump or could it be something else, this pump is only a month old, because my first one did this b4 where the pressure droped under wot, and i thought i had it fixed by getting a new pump? is this just bad luck or is something causing it? any help would be great
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Old 08-28-2008, 03:08 PM   #2
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ttt... not everyone at once
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Old 08-28-2008, 03:49 PM   #3
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Did you change the fuel filter? Possibly dirty filter makes sloggy.
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Old 08-28-2008, 04:26 PM   #4
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i changed that about 2 months ago
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Old 08-28-2008, 04:57 PM   #5
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check ur pressure regualtor it may b clogged, however it sounds likt the hose tht goes from the pump to the sending unit is either loose, or has a hole or some kind od slit in it and is leaking fuel back into the bucket....whn u changed out ur pump b4 did u overtighten the screw tht hold the hose to the top of the sending unit
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Old 08-28-2008, 06:02 PM   #6
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Quote:
Originally Posted by LS184 View Post
check ur pressure regualtor it may b clogged, however it sounds likt the hose tht goes from the pump to the sending unit is either loose, or has a hole or some kind od slit in it and is leaking fuel back into the bucket....whn u changed out ur pump b4 did u overtighten the screw tht hold the hose to the top of the sending unit
i just went out and pulled the regulator off and blew through it, put it back on turned the key forward and got like 56psi, cranked it and it dropped to 40 cranking then came back up when car started, idled for a min i walked away and it stalled out and is only getting like 4lbs now. i hope i didnt f up the regulator doing this, is there anything you can do wrong with it?

i checked the hose when it first broke down before i had it towed bc the hose on my first pump tore twice around the clamp so it was the first thing i checked.

i guess its just the pump but still wondering what is causing it to fail
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Old 08-28-2008, 09:44 PM   #7
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no u cant **** up ur regulator doin tht, ive done it alot, just make sure u put it back in the right way, also did u do any tipe of upgraded wireing harness whn u did ur pump? is ur pump overheating? when i did my racetronix pump i bought the wire harness as well cause a higher flowing pump requires a little more volts, do u have a voltmeter? i whould take a voltmeter to ur pump and c, if its low u could b a bad pump, it just seems odd cause like u said u just put it in
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Old 08-28-2008, 11:37 PM   #8
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Quote:
Originally Posted by LS184 View Post
no u cant **** up ur regulator doin tht, ive done it alot, just make sure u put it back in the right way, also did u do any tipe of upgraded wireing harness whn u did ur pump? is ur pump overheating? when i did my racetronix pump i bought the wire harness as well cause a higher flowing pump requires a little more volts, do u have a voltmeter? i whould take a voltmeter to ur pump and c, if its low u could b a bad pump, it just seems odd cause like u said u just put it in
^^^^I agree with LS184, best way for you to do checking on fuel pressure reg../ that what I thought to regulator must be bad or trick on you. no matter if it been new or replaced. Y have to check on fuel pressure (PSI)or wiring (OHM).
Good Luck...
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Old 08-29-2008, 12:24 AM   #9
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Quote:
Originally Posted by Jeff Smith View Post
^^^^I agree with LS184, best way for you to do checking on fuel pressure reg../ that what I thought to regulator must be bad or trick on you. no matter if it been new or replaced. Y have to check on fuel pressure (PSI)or wiring (OHM).
Good Luck...
**** man where u hammered when u wrote tht
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Old 08-29-2008, 07:29 AM   #10
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Let me guess, it's a Walbro??
If so:
http://www.turbobuick.com/forums/sea...earchid=790160
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Old 08-30-2008, 10:48 AM   #11
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Quote:
Originally Posted by Old Geezer View Post
Let me guess, it's a Walbro??
If so:
http://www.turbobuick.com/forums/sea...earchid=790160
yes its a walbro and that thread did me no good it went to a sign in page
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Old 08-30-2008, 11:08 AM   #12
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Talking Sorry.

Quote:
Originally Posted by blue99fbody View Post
yes its a walbro and that thread did me no good it went to a sign in page
didn't see the pump listed in your signature.
Try this link. It worked when I posted it.
http://www.turbobuick.com/forums/gen...o-failure.html
The other Buick board has thread[s] about this pump, also.
www.turbobuicks.com
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Old 08-30-2008, 04:39 PM   #13
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my car is doing the same thing i cant find what is wrong. I tryed a new fuel pump and hot wire kit, new regutor, new battery. Any one have a guess on what could be thanks sean
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Old 08-30-2008, 05:28 PM   #14
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do you have the racetronix wiring? mine did that to and it turned out the power wire was touching my header and grounded it out. check your wires.
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Old 08-30-2008, 05:31 PM   #15
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Quote:
Originally Posted by stmz28 View Post
my car is doing the same thing i cant find what is wrong. I tryed a new fuel pump and hot wire kit, new regutor, new battery. Any one have a guess on what could be thanks sean
did you test your alternator?
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Old 08-30-2008, 09:35 PM   #16
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Quote:
Originally Posted by LS184 View Post
**** man where u hammered when u wrote tht
[


Quote:
Originally Posted by Old Geezer View Post
didn't see the pump listed in your signature.
Try this link. It worked when I posted it.
http://www.turbobuick.com/forums/gen...o-failure.html
The other Buick board has thread[s] about this pump, also.
www.turbobuicks.com
Yeah, What i thought that. I surpirsed of Walbro..Thanks for sharing...That Link is great information of WAlbRO...Thanks

Quote:
Originally Posted by Dark Shadow View Post
do you have the racetronix wiring? mine did that to and it turned out the power wire was touching my header and grounded it out. check your wires.
Thanks for input so I will notify to my friends, have been trouble with Walbro fuel pump (MADE in CHINA).
THANKS for INPUT
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Old 09-13-2008, 02:38 PM   #17
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did any one find out what was wrong my car is still doing it.
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Old 09-13-2008, 03:38 PM   #18
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fyi, the regulator is in the tank on the sending unit.
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Old 09-13-2008, 03:38 PM
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