gas gauge is never at full

[KwlAznKid]

whenever i fill the car up with gas i just put the gun in and let it sit until it pops by itself, however when i turn the car on it's never at the complete top. here's a pic i took today right after i got in the car after filling it up.. anyone know what the problem could be?

thx

[Dwiggy]

My 99 996 does the same thing. I think the car is not designed to vent for California style pumps that completely cover the fill spout.

[violaGT3]

whenever i fill the car up with gas i just put the gun in and let it sit until it pops by itself, however when i turn the car on it's never at the complete top. here's a pic i took today right after i got in the car after filling it up.. anyone know what the problem could be?

thx

It can be a few things.

One. the neck design in the Porsche could be restrictive or have something slightly blocking it and cause the pump to release prematurely. (You may want to carefully (top off) the tank by watching the gun as you moderatly squeeze to slowly fill the tank.)

New thought, if your pumps have the foreskin, dont put the nozzle all the way in the filler, allow for room to breathe.

(Good Point Rattles)

Two, there could be petroleum residue on the rheostat (level mechanism) in the tank preventing it from reading in the lower position. This could be from being stored for an extended period of time in the car's life, doesn't need to be enough to foul the car just enough to coat part of the rheostat, and seeings how full registers at the bottom of the rheostat, it is likely to be the issue.

(my recommendation is to use a good grade system cleaner and drive it like you hate it, or love it?)

Three, You have a stuck needle on your guage cluster.

(Umm beat it like you hate it, or love it?)

Four, you have some kind of crazy wiring connection issue causing it to misread.

(IMO this is a total longshot and should not be considered until you get to the point of replacement, then just check the connections)

HTH G/L chilly yellow

Edited July 9, 2009 by ViolaGT3

[larez2]

I can't explain the technical reason behind it, but just run your tank down more before your next fill up and I bet the guage will show more full when you fill it up the same way. I used to fill up my tank regulary when it only needed 12 gallons. Gradually, the guage showed less "full" each time I filled it up, so I ran it more empty, like 15-16 gallons needed to fill it up few times in a row and each time I filled it up after running it down towards empty more, the guage registered more full after filling up. Of coarse you never want to run out of gas though!!!!

[RFM]

In some cases, the floater arm on the pump unit will get stuck behind a fuel line inside the tank, especially after a fuel pump replacement.

[Dennis C]

This happens to me at certain gas stations moreso than others. I think it has to do with the pump sometimes, so you might try different pumps and see if the result is the same.

[Loren]

whenever i fill the car up with gas i just put the gun in and let it sit until it pops by itself, however when i turn the car on it's never at the complete top. here's a pic i took today right after i got in the car after filling it up.. anyone know what the problem could be?

thx

C4 or C4S?

If so, read the section in your Owners Manual about refilling when the tank is very low.

[jgriffin56]

Are you using the same gas station and possibly the same pump for fill-ups. Sometimes we are creatures of habit. If I have problems with certain pumps , I simply turn the pump nozzle upside down or sideways, whatever works, manually filling tank with finger on trigger,and the gas eventually will fill to the top. Be careful to hold the pump with both hands to prevent it slipping or dropping, resulting in damage to the paint. JG (04 C4S)

[violaGT3]

whenever i fill the car up with gas i just put the gun in and let it sit until it pops by itself, however when i turn the car on it's never at the complete top. here's a pic i took today right after i got in the car after filling it up.. anyone know what the problem could be?

thx

C4 or C4S?

If so, read the section in your Owners Manual about refilling when the tank is very low.

Really? . . . these things are just laden with tweeks.

[Dennis C]

I went to a different gas station last night to fill up, and I did get a completely full tank.

[dr914jr]

In some cases, the floater arm on the pump unit will get stuck behind a fuel line inside the tank, especially after a fuel pump replacement.

I have seen this same issue many times. I actually did it to myself once.