Fuel Gauge Issue

[Gorgon]

We've taken two long trips with the C5 since we've gotten it. On both trips, when the fuel level gets to a quarter tank the DIC makes a "ding" and then the gauge falss to empty. After about 15 seconds, there is another "ding" and the DIC reads LOW FUEL and the "Check Gauges" light comes on in the instrument cluster. If the car is shut off and turned back on the fuel level reads the quarter tank that it has in the tank.

I have't seen this issue in city driving. Just driving on long trips. Any ideas?

Leon

 

[AZMike]

I had the exact same issue - guage would read random below 1/4 tank and drop to 'E' when driving for no reason.

It took a software update, a new fuel tank and 2 new sending units to fix my problem. At least it was all under warantee. GM has many issues with their fuel sending units, and it's even worse with the fomulation of gas we use in the Phoenix area.

Try the update first - if that doesn't fix it, you'll likely need new fuel sending units as well. I hope you're still under warantee.

Mine is much better now, but it does not seem to be totally accurate when above 1/2 tank anymore. That's OK - I'd rather it be acurate when below 1/4 tank as I have a nast habit of putting off trips to the gas station until the last possible moment (or couple of miles).

 

[Tuna]

My 03 did something similar. The dealer found fuel sending unit codes stored and replaced the offending sending unit.

 

[RED C-5 OF Jax]

When your tank gets to 1/2 just fill it up. Use Amoco 93 !!!!

 

[Gorgon]

I'll check for codes. Sadly, I'm out of warranty and it really isn't much of a problem as it only happens on long trips for some reason. I've never seen this happen on the local roads for short trips.

Leon

 

[AZMike]

When your tank gets to 1/2 just fill it up. Use Amoco 93 !!!!

I wish! The best we can get here in Phonix is 91. And we're getting raped for that. I'm sure you've seen us on the news.

Lucky I have a Costco membership - it's only $2.09 there - it's at least $2.25 everywhere else.

 

[fop91]

Fuel Guage

I just got my 2004 Cp. Dealer filled my tank that was on empty (sunoco ultra). When Gauge went to 3/4 tank it dropped to empty. Went back to dealer the next day they reprogrammed the code and said it will be ok. The next day at 1/2 tank the guage went back down to empty. Back to dealer they said they have to order new sensor in but the wharehouse idoes not have any. I got a new 2004 with 120 miles on it and no gas guage. I have read a lot of posts here about sensor problems but has anyone with a 2004 had simular problems.
Thanks

 

[Gorgon]

I checked the codes this evening and have a PCM code P1431 which is a Fuel Level Sensor 2 Circuit Performance. Now I need to the service manual to tell me with part is giving me problems.

Can anyone help?

Leon