TPI Tuned Port Injection discussion and questions. LB9 and L98 tech, porting, tuning, and bolt-on aftermarket products.
Sponsored by:
Sponsored by:

Fuel Pressure drops immediatley

Thread Tools
 
Search this Thread
 
Old Sep 22, 2003 | 03:49 PM
  #1  
strider681's Avatar
Thread Starter
Junior Member
 
Joined: Jan 2002
Posts: 98
Likes: 0
Car: '87 Pontiac Trans Am GTA
Engine: 350 5.7L TPI (L98)
Transmission: 700R4
Fuel Pressure drops immediatley

Hey guys, I have a 87 trans am TPI 5.7L and here is my problem. Comming out of my complex friday my car dies in the middle of a turn. well I get it over to the side of the road and start checking it out. first thing i hooked up a fuel pressure guage and read 0 psi. so i replace fuel pump relay, now get 41 psi while pump runs, then drops quickly to 0. now i took the old feul pump relay, took the cover off, and noticed when i remade the connection it would hold the pressure. so it's only holding when the pump is running. just to make sure i replaced oil pressure/fuel pump switch located near oil filter. no change. rebuilt pump relay connector, no difference. took fuel rail completely apart, replaced all o-rings and pressure regulator, no difference. at this point, the only thing left seems like the pump itself. i read in another post that there is a built in check valve for the pump? sounds like it may be it. i was also wondering if anyone knew if the tank pressure control valve hooked to the canister could affect this?? last thing, in order to check if injectors are laeking, do you have to have the wiring connected? any help is definat;ey appreciated, I'm almost at my wits end!
Reply
Old Sep 23, 2003 | 05:17 AM
  #2  
Viprklr's Avatar
Supreme Member
20 Year Member
iTrader: (5)
 
Joined: Feb 2002
Posts: 3,462
Likes: 4
From: N. Illinois
Car: 92 GTA/ 00 TA
Engine: 383/350
Transmission: 700R4/T-56
Re: Fuel Pressure drops immediatley

Originally posted by strider681
last thing, in order to check if injectors are laeking, do you have to have the wiring connected?
Yes. Lift the rail with everything connected so that you can see the spraying ends of the injectors. Prime the system and see if there's any leaking.
Reply
Old Sep 25, 2003 | 08:39 PM
  #3  
strider681's Avatar
Thread Starter
Junior Member
 
Joined: Jan 2002
Posts: 98
Likes: 0
Car: '87 Pontiac Trans Am GTA
Engine: 350 5.7L TPI (L98)
Transmission: 700R4
alrighty here is the skinny, after putting my car back together and trying to crank it, the fuel pressure stays right about 40. Now I noticed there was no spark, (which I should have checked frist) so I found the distributer control module was bad. at Autozone they can test those things. only 23 bucks for the part. so this was my problem all along.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
92camaroJoe
TBI
32
Jul 29, 2023 07:57 PM
R3500
Engine/Drivetrain/Suspension Wanted
1
Aug 17, 2015 12:16 PM
wayshegoes
Tech / General Engine
8
Aug 17, 2015 12:00 PM
92camaroJoe
Tech / General Engine
6
Aug 13, 2015 06:07 AM
Kaweh
TBI
3
Aug 9, 2015 02:54 PM




All times are GMT -5. The time now is 09:20 PM.