C5 Erratic Fuel Gauge Problem
Discussion
There have been many, many, many reports of fuel gauge problems in the C5. They show up in a lot of C5s built from 1997 to 2002. The problems usually show up when it is less than half full, either the fuel gauge makes a dive for the empty mark when there are still 3-4 gallons left or it sticks at a quarter full even when there is nothing left !
GM made a number of attempts to fix it. In cars built before 2001 the answer seems to be to replace the fuel tank senders on both the right and left tanks. This didn't work for everyone though.
The next solution GM came up with was to recalibrate the fuel system via software which again solved some but not everybody's problems.
I have not heard of any fuel gauge issues from the 2003 models onwards so maybe they've finally resolved the issue.
If your car is under warranty then I'd recommend going to an official dealer and getting it sorted out that way. If not then there are a couple of other options.
I had the problem show up when my 2002 C5 was 14,000 miles old and at first the gauge dived to zero, then it stayed above halfway for too long. I tried putting in a good dose of fuel system cleaner and that removed the problem. At the time I suggested that putting a dose of cleaner in every 10,000 miles would be a good piece of precautionary maintenance. Well, of course I didn't follow my own advice and 11,500 miles later I had exactly the same problem ! I used the fuel system cleaner again and the problem has gone away again.
The final option is one that will be second nature to any motorcyclist - reset your trip meter whenever you fill up. I get 26 MPG on average and know that I can safely get 300 miles out of a full tank. I'm happy doing 360-380 miles when driving gently. Check the trip meter occasionally and refill once you get past your comfort mark.
From my experience an extra indicator that will show when you are down below 9 litres remaining in the tank is when the engine cuts during high-G right hand corners !
GM made a number of attempts to fix it. In cars built before 2001 the answer seems to be to replace the fuel tank senders on both the right and left tanks. This didn't work for everyone though.
The next solution GM came up with was to recalibrate the fuel system via software which again solved some but not everybody's problems.
I have not heard of any fuel gauge issues from the 2003 models onwards so maybe they've finally resolved the issue.
If your car is under warranty then I'd recommend going to an official dealer and getting it sorted out that way. If not then there are a couple of other options.
I had the problem show up when my 2002 C5 was 14,000 miles old and at first the gauge dived to zero, then it stayed above halfway for too long. I tried putting in a good dose of fuel system cleaner and that removed the problem. At the time I suggested that putting a dose of cleaner in every 10,000 miles would be a good piece of precautionary maintenance. Well, of course I didn't follow my own advice and 11,500 miles later I had exactly the same problem ! I used the fuel system cleaner again and the problem has gone away again.
The final option is one that will be second nature to any motorcyclist - reset your trip meter whenever you fill up. I get 26 MPG on average and know that I can safely get 300 miles out of a full tank. I'm happy doing 360-380 miles when driving gently. Check the trip meter occasionally and refill once you get past your comfort mark.
From my experience an extra indicator that will show when you are down below 9 litres remaining in the tank is when the engine cuts during high-G right hand corners !
kenski said:
basically GM simply recommended that you didn't use these brands of fuel...
-kenski
...but since the oil companies indulge in swap arrangements the fuel you get is most likely to come from the owner of your nearest refinery rather than the brand owner of the petrol station. Having said that I have noticed the problem is more likely to occur after I have filled up at an Esso station than anywhere else.
It was an American one that I got through Demon Tweeks. Redline Fuel System cleaner (not just injectors but the whole system). I tried the Redex equivalent recently and had a recurrence of the gauge problem a short while after.
As GM do seem to have fixed the issue now after a number of attempts I am seriously considering making a warranty claim and getting it fixed the official way.
As GM do seem to have fixed the issue now after a number of attempts I am seriously considering making a warranty claim and getting it fixed the official way.
GM had a number of different tries at fixing the fuel gauge problem. Changing the sender in the right hand tank, changing the sender in the left hand tank, changing both senders in both tanks, updating the computer to interpret the fuel levels differently (aka flashing the PCM), updating the computer and changing the senders...
A competent GM garage can find the latest software updates for a vehicle here http://calid.gm.com/vci/VINEntryPre.do
It seems like there's quite a few for my car, my ABS is a bit aggressive at times so I think I'll ask for that to be done too ! I think a lot depends on when your car was built as to which remedy should be applied. Reflashing the PCM so that it uses different voltages to interpret sender information is the first solution, replacing the senders is a long job and probably only one that you and any garage would only want to do if absolutely necessary.
Here's some background reading: http://forums.corvetteforum.com/zerothread?id=776800&postid=1546771552#1546771552
A competent GM garage can find the latest software updates for a vehicle here http://calid.gm.com/vci/VINEntryPre.do
It seems like there's quite a few for my car, my ABS is a bit aggressive at times so I think I'll ask for that to be done too ! I think a lot depends on when your car was built as to which remedy should be applied. Reflashing the PCM so that it uses different voltages to interpret sender information is the first solution, replacing the senders is a long job and probably only one that you and any garage would only want to do if absolutely necessary.
Here's some background reading: http://forums.corvetteforum.com/zerothread?id=776800&postid=1546771552#1546771552
Here's a Technical Service Bulletin number to quote to your favourite garage:
Erratic Fuel Gauge Reading (Reprogram the PCM) #02-06-04-010A - (06/27/2003) 1999-2002 Chevrolet Corvette
This bulletin is being revised to add models and update the Correction and Warranty Information. Please discard Corporate Bulletin Number 02-06-04-010 (Section 06- Engine).
Condition
Some owners may comment about the fuel gauge intermittently indicating an empty reading and then return to the correct fuel level indication.
Cause
This condition may result when fuel blends containing aggressive sulphur compounds react with the fuel sender assembly, which may result in voltage spikes being induced on the fuel level signal to the PCM. Use of another fuel blend may reverse this reaction and return the system to normal operation.
Correction
Reprogram the PCM with the new service calibration which is available in the June 2003, Techline® TIS release sent to the dealers on 6/28/03. Use the TIS Version 7 or later data update.
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation
Description
Labor Time
J6354
Powertrain Controller - Reprogram
Use Published Time
Erratic Fuel Gauge Reading (Reprogram the PCM) #02-06-04-010A - (06/27/2003) 1999-2002 Chevrolet Corvette
This bulletin is being revised to add models and update the Correction and Warranty Information. Please discard Corporate Bulletin Number 02-06-04-010 (Section 06- Engine).
Condition
Some owners may comment about the fuel gauge intermittently indicating an empty reading and then return to the correct fuel level indication.
Cause
This condition may result when fuel blends containing aggressive sulphur compounds react with the fuel sender assembly, which may result in voltage spikes being induced on the fuel level signal to the PCM. Use of another fuel blend may reverse this reaction and return the system to normal operation.
Correction
Reprogram the PCM with the new service calibration which is available in the June 2003, Techline® TIS release sent to the dealers on 6/28/03. Use the TIS Version 7 or later data update.
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation
Description
Labor Time
J6354
Powertrain Controller - Reprogram
Use Published Time
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