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Car hard to start...Not Holding fuel pressure.

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Old 05-07-2005, 09:18 PM
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Default Car hard to start...Not Holding fuel pressure.

I have a fuel pressure pillar gauge..that normally reads out to 60-62psi of pressure. WEll today it was hard to start..and on the 3rd turn..it cranked..but only had about 25-30psi reading of fuel psi. Once i turn the car off..the pressure is gone. Usually the gauge will read pretty high for a good 5-10 mins or so.

I just changed the fuel filter, i have a walboro 255 pump, The injectors only have ruffly 20-30K on them. Would could be the problem?

Car has a NX wet kit installed..but has never been actually sprayed. All ive done with the nitrous kit is test the purge, and make sure it sprayed correctly..by holding the nozzle in the air. Any ideas? Please help.

1999 Trans Am WS6, M6, 66K miles. Bolt on motor.
Old 05-08-2005, 11:16 AM
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TTT!!! Someone had to of been threw this...is the fuel pressure regulator bad? what could it be? The pump i can hear start up and work..and im just not getting pressure.
Old 08-19-2005, 11:56 PM
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since pressure immediately goes away... my guess is a bad check valve... if it was an injector it would leak down, but not immediately
Old 08-22-2005, 08:10 PM
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Originally Posted by SporkLover
since pressure immediately goes away... my guess is a bad check valve... if it was an injector it would leak down, but not immediately
ditto
Old 08-23-2005, 06:46 AM
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I have had this problem before at my shop, and it turned out to be a leak in the rubber fuel line inside the fuel tank, where it is attached to the in tank fuel pump. When the engine is turned off, the pressure is relieved, which takes running the pump for several seconds necessary to build up fuel pressure. Bob
Old 08-23-2005, 08:36 AM
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A drooling injector though would make for some hard
starting and leakdown. If you can get the rails off and
keep the injectors on them, key on, key off, you should
see nothing out of any of them. If one drips then it's bad.
Use a couple of towels on a cold motor. If nothing easy
turns up you might want to check this.
Old 08-23-2005, 04:46 PM
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Sounds like the rubber line in the tank might of ripped.
Old 08-28-2005, 01:24 PM
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have had this problem 3 times in my father in laws model a (383 tpi w/walbro 255) first 2 times it was the rubber split in the tank....this time (just this morning) it was the pump itself.



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