Problem with gas gauge or tank(s)
Thread Starter
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 787
From: Lebanon Township New Jersey
Problem with gas gauge or tank(s)
I have a 2004 coupe, original owner, 54K miles. Lately when the gas gauge is reading 1/4 and I attempt to fill the tank, it will only take about 6 gallons before the pump shuts off. I tried adding more at that point and the pump shuts down as if gas is at the level of the fill nozzle. The gauge reads just over 1/2 at that point. Is this a problem with gas transfer between the 2 tanks, or a gauge problem?
I always use 93 octane, top tier gas, usually Sunoco. I also add Techron every 6 months. Any ideas?
I always use 93 octane, top tier gas, usually Sunoco. I also add Techron every 6 months. Any ideas?
Le Mans Master
Joined: Jan 2004
Posts: 9,488
Likes: 1,743
From: Knoxville Tn
I have a 2004 coupe, original owner, 54K miles. Lately when the gas gauge is reading 1/4 and I attempt to fill the tank, it will only take about 6 gallons before the pump shuts off. I tried adding more at that point and the pump shuts down as if gas is at the level of the fill nozzle. The gauge reads just over 1/2 at that point. Is this a problem with gas transfer between the 2 tanks, or a gauge problem?
I always use 93 octane, top tier gas, usually Sunoco. I also add Techron every 6 months. Any ideas?
I always use 93 octane, top tier gas, usually Sunoco. I also add Techron every 6 months. Any ideas?
Thread Starter
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 787
From: Lebanon Township New Jersey
Wow. Thanks for the help so far.
Car is parked on level ground.
Pressing reset with engine running didn't change gauge reading.
Pulled the codes and got these:
AO LDCM U1064H
A1 RDCM U1064H
99 HVAC 3 codes: BO 361H, BO 363H and BO 367H
Driving about 120 miles while the gauge drops to 1/4. About the normal rate.
Car is parked on level ground.
Pressing reset with engine running didn't change gauge reading.
Pulled the codes and got these:
AO LDCM U1064H
A1 RDCM U1064H
99 HVAC 3 codes: BO 361H, BO 363H and BO 367H
Driving about 120 miles while the gauge drops to 1/4. About the normal rate.
Last edited by BKbroiler; Jun 29, 2018 at 03:55 PM.
Thread Starter
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 787
From: Lebanon Township New Jersey
Thread Starter
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 787
From: Lebanon Township New Jersey
Next time the gauge gets down to 1/4 tank you might want to try pulling codes with the engine running before you turn off the ignition. To pull codes with the engine running you need to use the RESET button to clear any messages displayed in the DIC and then pull codes as normal.
If the fuel level sensors are an issue I would expect to see one or more PCM codes stored. I have seen codes on the C5 disappear once the engine is shut off and then the key returned to the ON position to pull the codes.....
If the fuel level sensors are an issue I would expect to see one or more PCM codes stored. I have seen codes on the C5 disappear once the engine is shut off and then the key returned to the ON position to pull the codes.....
At 1/4 tank I'll pull codes with the engine running.
Meanwhile I will dump in a couple bottles of Techron.
Le Mans Master
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From: Virginia
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Just FYI there was a recall for a fuel tank issue on a limited number of 04 Vettes (mine was one). There is also a common issue with the plastic tubes that transfer fuel from one tank to the other. However, if you have either of those issues, you'll smell gas after having the car in your garage for awhile. I hope this isn't your issue as it is pricy to fix.
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I would definitely do the Techron routine (maybe a couple of times) and see if that clears the sulfur buildup that may be on the fuel sending unit.
And moving this over to the C5 Tech section.
And moving this over to the C5 Tech section.
Thread Starter
Le Mans Master
Joined: May 2002
Posts: 5,086
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From: Lebanon Township New Jersey
Definitely not smelling gas while the car is sitting in the garage. If it is a transfer problem then I suppose I might be able to use only 1 tanks capacity? I will try large doses of Techron for now. Thanks for all the suggestions.
Safety Car
Joined: Dec 2010
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From: Fords, NJ
Just FYI there was a recall for a fuel tank issue on a limited number of 04 Vettes (mine was one). There is also a common issue with the plastic tubes that transfer fuel from one tank to the other. However, if you have either of those issues, you'll smell gas after having the car in your garage for awhile. I hope this isn't your issue as it is pricy to fix.
The extended warranty was for 10 years or 100k Miles....That expired LONG TIME AGO.
All of our cars are way past the 10 yr old mark. GM will do nothing for you and it's on your dime to get it repaired.
Last edited by SG Lou; Jun 30, 2018 at 03:47 PM.
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Yup!
There NEVER was a recall for the fuel tank issues on the 2004 C5. GM did issue an extended warranty to owners of C5's in the following VIN range:45110258 through 45125500
The extended warranty was for 10 years or 100k Miles....That expired LONG TIME AGO.
All of our cars are way past the 10 yr old mark. GM will do nothing for you and it's on your dime to get it repaired.
The extended warranty was for 10 years or 100k Miles....That expired LONG TIME AGO.
All of our cars are way past the 10 yr old mark. GM will do nothing for you and it's on your dime to get it repaired.
Plus, the problem being experienced was one involving fuel seepage/leakage, and had nothing to do with fuel level sensor or pump issues.
Race Director
Joined: Nov 2003
Posts: 16,068
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From: Bergen county NJ
Next time when you are filling the car with gas...turn the nozzle upside down. It’ll fill up then.
Instead of the handle facing down , face it up to the sky with the nozzle in the gas tank.
just my experience.
let us know if that works for you.
Instead of the handle facing down , face it up to the sky with the nozzle in the gas tank.
just my experience.
let us know if that works for you.
Last edited by JerriVette; Jun 30, 2018 at 06:34 PM.
Thread Starter
Le Mans Master
Joined: May 2002
Posts: 5,086
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From: Lebanon Township New Jersey
Thanks for the pump nozzle suggestions. I have experienced all that myself so I did try different pumps at different stations, moving the nozzle etc.
Here is the latest development: THE GAUGE IS NOW WORKING NORMALLY. I had added 2 more bottles of Techron. Gauge was reading just above 1/2. Drove about 120 miles, gauge down to 1/4. Went to a different Sunoco station to fill it and I was surprised to see it take 12 gallons (would only take 6 previously). Started the engine and the gauge moved to the full mark. Drove about another 80 miles and the gauge has dropped to about 7/8, like normal. I'm happy about this but still wondering what was happening. Seems like the gas wasn't transferring between tanks during filling, Still, how does the gauge read 1/2 when that happens?
Here is the latest development: THE GAUGE IS NOW WORKING NORMALLY. I had added 2 more bottles of Techron. Gauge was reading just above 1/2. Drove about 120 miles, gauge down to 1/4. Went to a different Sunoco station to fill it and I was surprised to see it take 12 gallons (would only take 6 previously). Started the engine and the gauge moved to the full mark. Drove about another 80 miles and the gauge has dropped to about 7/8, like normal. I'm happy about this but still wondering what was happening. Seems like the gas wasn't transferring between tanks during filling, Still, how does the gauge read 1/2 when that happens?
Thread Starter
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 787
From: Lebanon Township New Jersey
8VETTE7 - Thanks for all that info. I have been reading up on this and your description is certainly accurate in describing how it was designed. It does seem like the heavy dose of Techron must have brought about the fix. It seems strange to me that there was no check engine light codes at all or other codes pulled through your method relating to fuel. I drove it again this morning and it still appears to be all good.
I will continue with Techron in each tankful for a while.
Thanks for all the responses on this.
I will continue with Techron in each tankful for a while.
Thanks for all the responses on this.