Fuel Gague Qeustion
Thread Starter
Racer
Joined: Apr 2005
Posts: 357
Likes: 1
From: Lenoir Tn
Fuel Gague Qeustion
I have a 04 Vert. Put about 20 dollars in it today and the gague went to completely empty. Then in about 3 minutes it goes to completely full. Then back to empty. Up on the dash says check gaguges. Whats going on?????
Race Director
Joined: Nov 2003
Posts: 12,346
Likes: 5
From: Mustang OK
Common problem often caused by gasoline with aggressive or higher levels of sulfur which can foul the fuel sending unit. Try running some Chevron Techron through your tank. Also, you may want to change to a different brand of gasoline or at least use a different filling station.
NOTE: Your car being an '04 has the newer design FFS fuel system that GM began installing in the C5 in mid model year 2003 and carried forward to the C6. There are several service bulletins out on the erratic C5 Fuel gauge problem which call for reprogramming the PCM. However, these service bulletins are for those C5's with the non-FFS fuel system and reprogramming the PCM for this reason is NOT recommended for those C5's with the newer FFS fuel system. You can read more about the new FFS fuel system at the following link:
2003 - 2004: Service Information: Fuel Tank System
Also, this has been a topic of any number of threads here in the past. Here are a few of the more recent ones:
Fuel Gauge Quit Working!!
99 c5 fuel gauge incorrect
99 c5 fuel gauge incorrect
Gas Gauge Problem
how much techron concentrate?
Gas guage acting up.
Gas Sensors Question
Hope this helps. Good luck!
NOTE: Your car being an '04 has the newer design FFS fuel system that GM began installing in the C5 in mid model year 2003 and carried forward to the C6. There are several service bulletins out on the erratic C5 Fuel gauge problem which call for reprogramming the PCM. However, these service bulletins are for those C5's with the non-FFS fuel system and reprogramming the PCM for this reason is NOT recommended for those C5's with the newer FFS fuel system. You can read more about the new FFS fuel system at the following link:
2003 - 2004: Service Information: Fuel Tank System
Also, this has been a topic of any number of threads here in the past. Here are a few of the more recent ones:
Fuel Gauge Quit Working!!
99 c5 fuel gauge incorrect
99 c5 fuel gauge incorrect
Gas Gauge Problem
how much techron concentrate?
Gas guage acting up.
Gas Sensors Question
Hope this helps. Good luck!
Last edited by GrayC5; May 29, 2006 at 08:12 PM.
Race Director
Joined: Nov 2003
Posts: 12,346
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From: Mustang OK
Originally Posted by 2000FRCZ19
GM quality sucks!! i have not had a functioning fuel guage in my car since i have had it....
Good luck.
Last edited by GrayC5; May 29, 2006 at 07:34 PM.
Drifting
Joined: Apr 2000
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From: Jeffersonville In
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A couple of years ago, here in the midwest we had the same problem. The problem was with many different models. The 98 Pace Car would drop to empty anytime you got below 3/4 of a tank. Wife's Chrysler would show between a 1/4 and a 1/2 and be empty. In this case , the culprit, was too much sulphur in Mobile/Ashland/Speedway/Marathon, gas. Those merged companies spent several million dollars repairing , fule sending units, and fuel pumps. Neither of those cars run on 87 octane. The Vette on 93 octane and the Chrysler runs on 89 octane. The problem was even more widespread on the cars that ran 87 octane.
Team Owner
Joined: Mar 2001
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From: small town in S.E Pa. PA
St. Jude Donor '03-'04
Originally Posted by 2000FRCZ19
GM quality sucks!! i have not had a functioning fuel guage in my car since i have had it. it says 3/4 when it is full and empty when it is 3/4 full or it says it is 1/2 when it has less than an 1/8. it has been to the steeler two times for the same problem and was never fixed. the sensor was replaced and a flash was done and still nothing worked. i didnt have time to be without the car so i didnt feel like fooling with the dealer anymore. i ran cleaner through it and still nothing. i just use my trip counter and dont worry about it. But since yours was working before the fuel up it could be just a simple case of needing to run a little techron through it. i have heard of several people having good luck with this. sorry to sound a little bitter but after the fuel guage problems and the clb problems and the window motor problems that GM service did not want to stand behind but would gladly fix for me if i gave them my entire bank account, i just needed to vent a little. i still love my car, i just hate the way GM will not admit to an on going problem and just fix it. give the techron a try it will more than likely clear up your problem.
would have them fixing it for free... The fuel gage problem is well documented, sulfer build up on the sweep is the cause and the fix is replacing it.. if they did that and it didnt work, they must have put in a bad sender...A new sensor would not be intermittant.. the sweep gets coated over time and them become a problem.. some parts of the sweep are not coated and you get a fuel reading..
Tech Contributor
Joined: Oct 1999
Posts: 41,058
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From: Charlotte, NC (formerly Endicott, NY)
Originally Posted by 2000FRCZ19
i am sorry for the off topic rant. 
i didnt mean to upset you guys. ( i didnt realize evil twin gets his retirement check from GM ) just joking so dont be offended. i will keep my rants about my opinion of GM's service to myself. the problem is i cant be without my car so more time in the service dept is unacceptable for me. i have since learned that many of my problems can be solved here.
many of the people that work for GM on here have been a great help to me.
i didnt mean to upset you guys. ( i didnt realize evil twin gets his retirement check from GM ) just joking so dont be offended. i will keep my rants about my opinion of GM's service to myself. the problem is i cant be without my car so more time in the service dept is unacceptable for me. i have since learned that many of my problems can be solved here. many of the people that work for GM on here have been a great help to me.Bill
