Rough running

1993 BUICK GRAN SPORT
85,644 MILES • 3.8L • 6 CYL • FWD • AUTOMATIC
Avatar
WEEKEND WRENCHER
  • MEMBER
  • 4 POSTS
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 10:49 PM
Advertisement
Avatar
HMAC300
  • CERTIFIED EXPERT
  • 48,601 POSTS
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 20, 2017 at 5:35 AM
Avatar
WEEKEND WRENCHER
  • MEMBER
  • 4 POSTS
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 5:07 PM
Advertisement
Avatar
HMAC300
  • CERTIFIED EXPERT
  • 48,601 POSTS
yep sounds like a fuel pump
Jul 22, 2017 at 6:04 AM
Avatar
WEEKEND WRENCHER
  • MEMBER
  • 4 POSTS
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 28, 2017 at 5:17 AM
Avatar
HMAC300
  • CERTIFIED EXPERT
  • 48,601 POSTS
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 28, 2017 at 6:35 AM
Avatar
WEEKEND WRENCHER
  • MEMBER
  • 4 POSTS
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 7:47 PM
Avatar
STRAILER
  • CERTIFIED EXPERT
  • 53,855 POSTS
Nice work, we are here to help, please use 2CarPros anytime.

Cheers, Ken
Jul 30, 2017 at 5:44 PM