5CHN3LL

After installing a new fuel pump in my '99 996 C4, I find that the fuel gauge is stuck at 3/4. From Googling and reading the Essential Companion I find that this can be an issue with the mk1 996 if battery power is lost when the fuel level is low, and I've done the things I could do (refill tank completely, disconnect battery overnight, pop off the fuel tank cover in the front trunk and verify that the electrical connectors are properly connected), but my gauge is still stuck at 3/4.

I have an appt Monday for with my shop so they can fix whatever's been done, but if anyone has a suggestion, I'd love to hear it. I'll be doing a long drive this weekend, and a working fuel gauge is a nice thing to have...

5CHN3LL

32 views and no answers? Y'all are killing me.

I ran out of gas last night due to this issue - and poor recordkeeping on my part since it's been non-functional - so it'll be really nice to get this fixed.

Byprodriver

Same thing happened to me a couple years after I got my 2000, well except I was on track in the desert at Willow Springs & the gas gauge showed 1/4 full which is what I shoot for on timed runs. The needs to be recalibrated with PST & a full tank.

targa996

I'm not sure about how Porsche sender works but I had Mercedes where the float ball inside the tank got gunked up and stuck... Solution was to dump a bottle of techron in the tank ... Fixed the problem for me ...

TomF

Check over on Renntech about this issue. It should have recalibrated when you did all the above things.
If it was stuck at 1/4, that would be one thing, but at 3/4 maybe as someone else said, the sender is stuck or has failed.

Best of luck. Let us know what it turns out to be.

Cheers,
TomF

fpb111

From Renntech.org
http://www.renntech.org/forums/topic...on#entry103124

If you disconnect the battery on a C4, C4S or TT with under 1/4 tank - you will need to get the tank re-calibrated using a PST2 or PIWIS.
Those cars use a "saddle bag" gas tank and the sensor is only on one side. So one side of the tank is "estimated" on the fuel gauge - based on the a specific amount of fuel in the tank at calibration time.
If you lose that calibration setting by disconnecting the battery (with a low tank) the tank/cluster has no guess as to remaining fuel and MUST be re-calibrated.

5CHN3LL

Cool. I'll present that to my indy on Monday.

fpb111

I think I read it assumes 19 liters in the tank after battery disconnect? Couldn't find it again. Might be a way to get it back on track. Empty tank add 19L disconnect battery.

5CHN3LL

Good news - honest indy disassembled and reassembled everything @ no charge, all is well once again.