Fueling & Injection Fuel Pumps | Injectors | Rails | Regulators | Tanks

Fuel pressure bleeding off

Thread Tools
 
Search this Thread
 
Old Apr 14, 2009 | 11:34 PM
  #1  
Ralls's Avatar
Thread Starter
TECH Fanatic
15 Year Member
iTrader: (32)
 
Joined: Oct 2005
Posts: 1,687
Likes: 0
From: Fairfax, Virginia
Default Fuel pressure bleeding off

My friend and I are trying to figure out an issue with his car. It is a 1989 Camaro with a ls1 swap in it. It has a Aeromotive FPR and a walbro 255 pump. A few times it has been sputtering and running bad and the fuel pressure would be down to like 7psi. Then we would turn the car off and 20 minutes later it will start right up with good fuel pressure. It happens when there is about 1/4 tank or below of fuel. I was thinking it's just from low fuel and he should keep more fuel in the tank. But there is another issue that still doesn't make since..

The fuel pressure bleeds off (engine off) rather quickly. I'm not sure what the spec is for these cars. It dropped from 55psi to 45 psi within 1 minute. It will continue to bleed all they way down to 5psi within about 10 minutes.
We pulled the return line off to see if it was leaking from there, it wasn't. Then we pulled the fuel rail off with the injectors attached to see if any were leaking, none were leaking. So the only thing left would be leaking at the pump. Well we dropped the tank and looked at the pump. Everything looked good, no cracks in hoses or loose wires. Any suggestions?
Reply




All times are GMT -5. The time now is 04:24 PM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE