1991 fuel pressure drops
07-18-2019, 08:58 PM
#1
1991 fuel pressure drops
started my 91 and it ran like crap and died wouldn't restart. so I put the fuel pressure gauge on it, turn key on jumps to 40psi then immediatly starts dropping. fuel pump was replaced last year. bad pump, injector staying open or pressure regulator? any help is appericiated
07-19-2019, 07:46 AM
#3
Burning Brakes
Member Since: Jan 2017
Location: Diamondhead Mississippi
Posts: 960
Received 236 Likes
on
171 Posts
St. Jude Donor '17-'18-'19-'20-'21-'22
The same thing happened to me except mine is maintaining pressure when running. Could be the check valve in the fuel pump which I believe is what happened with mine.Get someone to turn the key on and then immediately clamp off the supply line at the tank. If the pressure holds then it is not injectors or FPR.
07-20-2019, 12:29 PM
#4
Race Director
Member Since: Feb 2002
Location: Compound in the Grove, Ga.
Posts: 11,325
Received 910 Likes
on
583 Posts
2020 C3 of the Year Finalist - Unmodified
2019 C4 of Year Finalist (performance mods)
2018 C4 of Year Finalist
2015 C4 of the Year Finalist
St. Jude Donor '16
2020 C3 of the Year Finalist - Unmodified
I've also seen the clamp to the fuel line in the tank come lose or if you still have the plastic clamp they get old and come apart or if you did not replace the line they also get saturated over time get soft and split.