1982 fuel pressure issues
Thread Starter
7th Gear
Joined: Dec 2022
Posts: 7
Likes: 0
1982 fuel pressure issues
I have rebuilt the throttle bodies on the crossfire and also installed a new fuel pump and fuel filter. Fuel pressure is at 10. When I try to adjust it, it stays at 10 until the adjuster is completely maxed out, then it goes to 20. I am assuming that the spring may be weak and not applying the correct pressure to the diaphragm when adjusting.
Any other ideas?
Does anyone, anywhere sell just the springs? I cant find them so far.
Any other ideas?
Does anyone, anywhere sell just the springs? I cant find them so far.
Last edited by MrMadman; Jun 8, 2023 at 03:30 PM. Reason: forgot a detail
Safety Car
Joined: Nov 2005
Posts: 3,532
Likes: 1,185
From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
Just wondering... When you rebuilt the TBs, did you put the correct spring back in the rear TB? They are different springs and diaphragms as well. That's why I always tell people to do one TB at a time so you don't mix the parts up and put it back together wrong. Normally, the rear TB is a red or pink spring on an original GM TB. However, I have seen green springs as well. You might want to have a look and swap the springs. Correct pressure for a stock motor is 13psi as well. The issues you describe also sounds like the spring is going into coil bind and that's why it spikes up in pressure. Check the springs. 
Thread Starter
7th Gear
Joined: Dec 2022
Posts: 7
Likes: 0
Just wondering... When you rebuilt the TBs, did you put the correct spring back in the rear TB? They are different springs and diaphragms as well. That's why I always tell people to do one TB at a time so you don't mix the parts up and put it back together wrong. Normally, the rear TB is a red or pink spring on an original GM TB. However, I have seen green springs as well. You might want to have a look and swap the springs. Correct pressure for a stock motor is 13psi as well. The issues you describe also sounds like the spring is going into coil bind and that's why it spikes up in pressure. Check the springs.
I did do them one at a time, but the previous owner told me he rebuilt them also. So maybe he did switch them, very possible since I have been fixing some pretty funky things he did. I rebuilt them because of a gasket fuel leak and bad injector
Safety Car
Joined: Nov 2005
Posts: 3,532
Likes: 1,185
From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
Post back up what you find and if your issue changes after the spring swap. Also, I didn't mention that I have also seen a light blue spring before, but not entirely sure that came from an original TB or not. 30 years is a long time to remember what spring came out of what. 
Thread Starter
7th Gear
Joined: Dec 2022
Posts: 7
Likes: 0
Post back up what you find and if your issue changes after the spring swap. Also, I didn't mention that I have also seen a light blue spring before, but not entirely sure that came from an original TB or not. 30 years is a long time to remember what spring came out of what.
Thread Starter
7th Gear
Joined: Dec 2022
Posts: 7
Likes: 0
The Spring on the right was in the rear. Also the diaphragm on the right was in the rear which I believe is correct. The spring on the right is stiffer than the one on the left.
Last edited by MrMadman; Jun 11, 2023 at 09:07 PM. Reason: forgot text
Thread Starter
7th Gear
Joined: Dec 2022
Posts: 7
Likes: 0
Also the one on the left was on the front TBI. I have been looking through the GM shop manual and cannot for the life of me figure out if the previous owner may have switched these also when he rebuilt it. If he did then the diaphragms would not work correctly
Safety Car
Joined: Nov 2005
Posts: 3,532
Likes: 1,185
From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
Well, that's odd. They all look correct except for the sprig colors, so who knows what someone did in the past? I still think you have a spring issue. Let me dig through all my stuff and see what I have lying around. That comp diaphragm doesn't look good, but you said you were going to replace them anyway. Were you the one that did the rebuild recently? If so, what kit did you use?
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
7th Gear
Joined: Dec 2022
Posts: 7
Likes: 0
Well, that's odd. They all look correct except for the sprig colors, so who knows what someone did in the past? I still think you have a spring issue. Let me dig through all my stuff and see what I have lying around. That comp diaphragm doesn't look good, but you said you were going to replace them anyway. Were you the one that did the rebuild recently? If so, what kit did you use?
I have been finding numerous things on it that have been Jerry rigged and just done incorrectly. So when it comes to these TBI’s I wouldn’t be surprised if he swapped them out with something else. I do know that the block was changed at some point.
Thread Starter
7th Gear
Joined: Dec 2022
Posts: 7
Likes: 0
Thanks for the information. I sent you a PM also. I am going to check the fuel pressure before the fuel filter and make sure its not the new fuel pump I put in. Also ordering a new gauge just incase the one I have is bad and giving me an incorrect reading.