fuel tank gasket ???
Thread Starter
Racer
Joined: Mar 2004
Posts: 305
Likes: 0
From: Houston Texas
fuel tank gasket ???
I am changing out the rubber gasket that goes between the fuel tank and the filler neck.
Do I need to apply any sort of gasket sealant, or is the rubber itself sufficient, by itself?
Also, I have a code 54. If this gasket is bad, and is allowing fuel pressure to escape, could this be the cause of my code 54?
Do I need to apply any sort of gasket sealant, or is the rubber itself sufficient, by itself?
Also, I have a code 54. If this gasket is bad, and is allowing fuel pressure to escape, could this be the cause of my code 54?
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
I have never changed that gasket in the several times I've changed pumps. Codes get set when the ECM gets an out of parameter reading from a sensor. The only way that gasket could cause a code, is if you have a fuel tank pressure sensor. Your Factory Service Manual has a trouble shooting chart to lead you to the cause of the code, without buying unnecessary parts.
RACE ON!!!
RACE ON!!!
Thread Starter
Racer
Joined: Mar 2004
Posts: 305
Likes: 0
From: Houston Texas
I replaced the fuel guage sending unit, and noticed that the gasket was falling apart. The only thing holding it together was the fact that it was sandwiched between the fuel tank and the filler neck. Even if this isn't the 'code 54' problem, it still needs to be replaced.
With Code 54 being a fuel circuit problem, and since the fuel system is supposed to be pressurized, I figured that if the gasket was allowing the fuel pressure to slowly escape (like overnight), this may be my problem.
I can start my car easily if it has ran recently. But let it set overnight, and it may take me turning it over for 4 to 6 seconds before it starts up.
In any case, I will replace the gasket tonight.
What do y'all think?
With Code 54 being a fuel circuit problem, and since the fuel system is supposed to be pressurized, I figured that if the gasket was allowing the fuel pressure to slowly escape (like overnight), this may be my problem.
I can start my car easily if it has ran recently. But let it set overnight, and it may take me turning it over for 4 to 6 seconds before it starts up.
In any case, I will replace the gasket tonight.
What do y'all think?
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by 1slyder1
With Code 54 being a fuel circuit problem, and since the fuel system is supposed to be pressurized, I figured that if the gasket was allowing the fuel pressure to slowly escape (like overnight), this may be my problem.
What do y'all think?
What do y'all think?
RACE ON!!!
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
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
Drifting
Joined: Nov 2002
Posts: 1,593
Likes: 0
From: Mobile AL
St. Jude Donor '05
The generic code 54 is Fuel enable failure, and, yes, it is possible that loss of pressure in the fuel tank could have flagged a sensor to have the CCM show that code. Replace the gasket, reset the code and crank it up.
Melting Slicks
Joined: Aug 1999
Posts: 2,240
Likes: 42
From: Baltimore, MD USA
You didn't mention the year of your Vette. If this is for a 85, Code 54 is Low Voltage Fuel Pump Circuit.
The purpose for Code 54 is to detect a bad fuel pump relay.
If the engine is running, Code 54 will set if the voltage to the fuel pump is less than 2 volts for 1.5 seconds since the last reference pluse was received from the distributor.
When you turn the key to Run (engine not running) the ECM also expects the Fuel Pump to run for 2 seconds. If it doesn't see 12 volts to the fuel pump, Code 54 will set.
Most likely your problem is a bad fuel pump relay.
Not sure on a 85 but I think it's mounted on the firewall on the passenger side of the power brake booster.
The purpose for Code 54 is to detect a bad fuel pump relay.
If the engine is running, Code 54 will set if the voltage to the fuel pump is less than 2 volts for 1.5 seconds since the last reference pluse was received from the distributor.
When you turn the key to Run (engine not running) the ECM also expects the Fuel Pump to run for 2 seconds. If it doesn't see 12 volts to the fuel pump, Code 54 will set.
Most likely your problem is a bad fuel pump relay.
Not sure on a 85 but I think it's mounted on the firewall on the passenger side of the power brake booster.
Thread Starter
Racer
Joined: Mar 2004
Posts: 305
Likes: 0
From: Houston Texas
Hooked on Vettes-
Sorry about that. Yes, it is an '85 vette.
I replaced the relay about two years ago. Maybe it's time for another one.
Still gonna replace the fuel tank gasket, though. It's really in bad shape.
Everyone, I appreciate the input. Thank you very much.
Sorry about that. Yes, it is an '85 vette.
I replaced the relay about two years ago. Maybe it's time for another one.
Still gonna replace the fuel tank gasket, though. It's really in bad shape.
Everyone, I appreciate the input. Thank you very much.
Race Director
Joined: Dec 2000
Posts: 17,551
Likes: 26
From: El Paso Texas
One last footnote....when reinstalling, ensure the correct orientation of the "notch" in the gasket....upper right. It will fit other ways, but won't seal correctly. Here's some pics that might help.
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by Hooked on Vettes
When you turn the key to Run (engine not running) the ECM also expects the Fuel Pump to run for 2 seconds.
Also, I never suggested NOT replacing the gasket. I just said that *I* haven't needed to. If it is as screwed up as you say...definitely DO replace the gasket. The fumes that can leak out with a bad gasket can be extremely dangerous. You WILL not cure the cause of your code 54, though. If depressurizing the tank caused a code, you would get one at every fill up.
RACE ON!!!
Melting Slicks
Joined: Aug 1999
Posts: 2,240
Likes: 42
From: Baltimore, MD USA
Were taking about what can cause a Code 54
CFI-EFI You really need to chill out and read what I said instead of quoting partial statements like you have a habit of doing.
When you turn the key to run, it's obvious no distributor pulses will be present so the ECM will only energize the Fuel Pump relay for 2 seconds.
During the 2 second period, if the ECM sees no 12 volts on the Fuel Pump relay output, Code 54 will set.
CFI-EFI You appear by your posts to have a negative additude. Always ready to jump in to a post but offer little if any solutions.
Originally Posted by Hooked on Vettes
When you turn the key to Run (engine not running) the ECM also expects the Fuel Pump to run for 2 seconds. If it doesn't see 12 volts to the fuel pump, Code 54 will set.
When you turn the key to run, it's obvious no distributor pulses will be present so the ECM will only energize the Fuel Pump relay for 2 seconds.
During the 2 second period, if the ECM sees no 12 volts on the Fuel Pump relay output, Code 54 will set.
CFI-EFI You appear by your posts to have a negative additude. Always ready to jump in to a post but offer little if any solutions.
Last edited by Hooked on Vettes; Mar 10, 2005 at 04:25 PM.