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I did a search on this topic, but found no answers.

Recently my 2007 C4 fuel gauge started exhibiting odd behavior. When I fill the car up, the needle only goes to about 3/4 full. The fuel range will indicate something like 288 miles to go, and it will never change. If the actual fuel level falls below the 3/4 level, and I don't turn the car off, I THINK that the needle does not ever move, but if I turn the car off AFTER the actual fuel level falls beIow 3/4, and then turn the car on again, the fuel gauge will function normally until the next time that I fill up the car. I'm sure that I am actually filling the tank because of the amount of fuel going into the car. I'm guessing that something is wrong with the sending unit in the tank. Is there an easy way to troubleshoot this? I have a good DVM. Thanks.

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Thanks for the diagram. I will check the connectors.

Sounds like it is out of calibration to me. Did you let the tank run really low and then not fill it up completely?

It is possible that I did. This car is my track car / Sunday driver, and so it sits a lot. I almost always fill it full when I get gas, but once or twice recently I only put in 5 - 8 gallons because I was concerned about having the gas sit in the car for a couple of weeks. When I did a partial fill, I found that the "miles to go" would not calibrate correctly, and so I went back to filling the tank full. I can't remember if this current problem occured immediately after the partial fills.

Mike

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  • 3 months later...

Thanks for the diagram. I will check the connectors.

Sounds like it is out of calibration to me. Did you let the tank run really low and then not fill it up completely?

It is possible that I did. This car is my track car / Sunday driver, and so it sits a lot. I almost always fill it full when I get gas, but once or twice recently I only put in 5 - 8 gallons because I was concerned about having the gas sit in the car for a couple of weeks. When I did a partial fill, I found that the "miles to go" would not calibrate correctly, and so I went back to filling the tank full. I can't remember if this current problem occured immediately after the partial fills.

Mike

I seem to be experience the same problem...

And I also let the car run low in fuel and did not refill it all the way....

Any updates on this?

Thanks,

Gus

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  • 5 weeks later...

My 2001 C2 began experiencing this problem this week.

I did let the fuel level get really low, but did fill the tank full. However, upon the next fill up I noticed my gauge only read 3/4 full and began getting back flow like the tank is full.

Should I let the tank run really low again and fill completely?

Thanks for the diagram. I will check the connectors.

Sounds like it is out of calibration to me. Did you let the tank run really low and then not fill it up completely?

It is possible that I did. This car is my track car / Sunday driver, and so it sits a lot. I almost always fill it full when I get gas, but once or twice recently I only put in 5 - 8 gallons because I was concerned about having the gas sit in the car for a couple of weeks. When I did a partial fill, I found that the "miles to go" would not calibrate correctly, and so I went back to filling the tank full. I can't remember if this current problem occured immediately after the partial fills.

Mike

I seem to be experience the same problem...

And I also let the car run low in fuel and did not refill it all the way....

Any updates on this?

Thanks,

Gus

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  • Admin

My 2001 C2 began experiencing this problem this week.

I did let the fuel level get really low, but did fill the tank full. However, upon the next fill up I noticed my gauge only read 3/4 full and began getting back flow like the tank is full.

Should I let the tank run really low again and fill completely?

Thanks for the diagram. I will check the connectors.

Sounds like it is out of calibration to me. Did you let the tank run really low and then not fill it up completely?

It is possible that I did. This car is my track car / Sunday driver, and so it sits a lot. I almost always fill it full when I get gas, but once or twice recently I only put in 5 - 8 gallons because I was concerned about having the gas sit in the car for a couple of weeks. When I did a partial fill, I found that the "miles to go" would not calibrate correctly, and so I went back to filling the tank full. I can't remember if this current problem occured immediately after the partial fills.

Mike

I seem to be experience the same problem...

And I also let the car run low in fuel and did not refill it all the way....

Any updates on this?

Thanks,

Gus

C2/C2S gas tank is different from the C4/C4S gas tank.

In C4 it is a saddlebag tank with one part on each side of the front wheel drive - and the fuel level is only on one side.

C4/C4S fuel tank

post-1-0-34966700-1288884234_thumb.jpg

C2/C2S does not have this issue as it is all one tank.

C2/C2S fuel tank

post-1-0-03127100-1288884264_thumb.jpg

So, I think you may have another issue. Best to put Durametric or a PIWIS on the car and see what is really going on.

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  • 2 months later...

Loren, thanks.....it did turn out to be the E-6 fuse...it was blown

My 2001 C2 began experiencing this problem this week.

I did let the fuel level get really low, but did fill the tank full. However, upon the next fill up I noticed my gauge only read 3/4 full and began getting back flow like the tank is full.

Should I let the tank run really low again and fill completely?

Thanks for the diagram. I will check the connectors.

Sounds like it is out of calibration to me. Did you let the tank run really low and then not fill it up completely?

It is possible that I did. This car is my track car / Sunday driver, and so it sits a lot. I almost always fill it full when I get gas, but once or twice recently I only put in 5 - 8 gallons because I was concerned about having the gas sit in the car for a couple of weeks. When I did a partial fill, I found that the "miles to go" would not calibrate correctly, and so I went back to filling the tank full. I can't remember if this current problem occured immediately after the partial fills.

Mike

I seem to be experience the same problem...

And I also let the car run low in fuel and did not refill it all the way....

Any updates on this?

Thanks,

Gus

C2/C2S gas tank is different from the C4/C4S gas tank.

In C4 it is a saddlebag tank with one part on each side of the front wheel drive - and the fuel level is only on one side.

C4/C4S fuel tank

post-1-0-34966700-1288884234_thumb.jpg

C2/C2S does not have this issue as it is all one tank.

C2/C2S fuel tank

post-1-0-03127100-1288884264_thumb.jpg

So, I think you may have another issue. Best to put Durametric or a PIWIS on the car and see what is really going on.

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