Rough running

1993 BUICK GRAN SPORT
85,644 MILES • 3.8L • 6 CYL • FWD • AUTOMATIC
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WEEKEND WRENCHER
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Starts but runs real rough until it shuts off. can keep it running by pumping the gas peddle fast.

If I release the pressure on the shrader valve with key on will it continuously shoot out fuel?
Jul 19, 2017 at 3:49 PM
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HMAC300
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check fuel pressure with a gauge and scan for codes by crossing A and B with a paper clip with key on then either go to where are codes are under repair guides or get back with the number. auto parts rent gauge which should range 41-47 psi no less. Also, check for a vacuum leak as some of the older Buick's would crack the intake being plastic. See link.
https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator
Jul 19, 2017 at 10:35 PM
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WEEKEND WRENCHER
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Thank you it gave me a direction to go rented a pressure tester only getting 10 - 12psi at the Schrader valve . C/O pump and in line filter?
Thanks
The weekend wencher
Jul 21, 2017 at 10:07 AM
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HMAC300
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yep sounds like a fuel pump
Jul 21, 2017 at 11:04 PM
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WEEKEND WRENCHER
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Hi reading the istructionpapers that came with New fuel pump in said a bad oil pressure sensor could also cause a problem is this so?
Thanks the W.E.W.
Jul 27, 2017 at 10:17 PM
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HMAC300
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I don't think so if it powers up when you turn key on andyou only get 10-12 psi then it's the pump. the oil pressure switch keeps it running when you start the car
Jul 27, 2017 at 11:35 PM
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WEEKEND WRENCHER
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Hi changed the fuel pump, retested fuel pressure now reads 47-50psi running great thanks HMCA 300 you were most helpful thanks again.

The WeekendWrencher.
Oh yea now the Little woman wants to for drive on Sunday.
Jul 29, 2017 at 12:47 PM
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STRAILER
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Nice work, we are here to help, please use 2CarPros anytime.

Cheers, Ken
Jul 30, 2017 at 10:44 AM
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