1985 tpi fuel pressure issues
Thread Starter
Intermediate
Joined: May 2021
Posts: 31
Likes: 1
1985 tpi fuel pressure issues
I have had this car for 3 weeks now. Ran perfect for 2 days and now my fuel pressure is not going above 22psi. Turn the key on 22, start the car “hard to start” 22, rev it up and it completely stalls as if it almost dies 22psi. Gauge is working, I checked it in another vehicle.
went through two pumps and get the same exact results. Fuel line has been checked, fuel filter replaced, injectors are new.
what could be the issue
went through two pumps and get the same exact results. Fuel line has been checked, fuel filter replaced, injectors are new.
what could be the issue
Advanced
Joined: Sep 2010
Posts: 95
Likes: 3
From: Sharpsburg GA
Sounds like possible fuel pressure regulator. I’m dealing with mine. Borrow fuel pressure tester from parts store, go online and find fuel pressure measure and follow directions. As DIY goes on these cars its a pretty easy replacement. I
Pro
Joined: Aug 2020
Posts: 647
Likes: 126
From: Liliha Bakery stuffing my face with coco puffs!
Did you try clamping the return line as I've suggested in another thread to see if the fuel pressure will improve over 22 psi? If the Never Ever Worked pump is not up to the task, there's absolutely nothing you can do to make it increase in pressure. Something to look for...I've read that clamping the return and rechecking fuel pressure can net ~60 psi.
https://www.corvetteforum.com/forums...ator-help.html
https://www.corvetteforum.com/forums...ator-help.html
Pro
Joined: Aug 2020
Posts: 647
Likes: 126
From: Liliha Bakery stuffing my face with coco puffs!
22 psi is not enough pressure to unseat the spring in the FPR so clamping the return line probably won't tell you much which leads me to think something in the pressure side of the system is dumping the pressure at the injectors or in the tank itself. I do recall another check that you key on, fuel pressure indicated on the gauge and clamp pressure side to see if there's any leak down between pump and injectors/FPR. 
Drifting
Joined: Aug 2019
Posts: 1,339
Likes: 225
If you had leaking injectors, your plugs would be wet. What brand pump? Are you sure you clamped the correct line?
Hard to think you had 2 bad pumps. Try pulling the vacuum line to the regulator....is there fuel in it?
Hard to think you had 2 bad pumps. Try pulling the vacuum line to the regulator....is there fuel in it?
Last edited by Mrvettenick; May 29, 2021 at 05:41 PM.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Thread Starter
Intermediate
Joined: May 2021
Posts: 31
Likes: 1
1985 tpi
Guys, maybe the bad ground was in the relay??? I replaced it, pretty cheap part and replaced the pump for a 4th time in 3 weeks. Drove it 15 miles with no issues. Fuel pressure is holding at 43 psi now. Might have a fouled plug but other than that it was smooth. Thanks for the help
