Fuel level keeps dropping
Thread Starter
Instructor
Joined: Apr 2005
Posts: 137
Likes: 0
Fuel level keeps dropping
I just purchased a '99 black hardtop. I couldn't help but notice my fuel level drops significantly when I start the car in the morning. It is never at the same fuel level that it was at when I shut the car off for the night. While driving, the car does consume its normal share of fuel. I do see the needle drops normally as it should. But, like I said, when I return to startup, it drops even more. Do I have a sending unit problem? Note: the fuel range will also be significantly less at startup
ex: When I got home last night, the fuel range was at 287. This morning at startup, the range dropped to 269 along with the needle. The car sat there all night.
Please help
ex: When I got home last night, the fuel range was at 287. This morning at startup, the range dropped to 269 along with the needle. The car sat there all night.
Please help
Race Director
Joined: Mar 2005
Posts: 14,440
Likes: 3
From: MD
St. Jude Donor '11
You have two plactic gas tanks that sit behind the seats. The car automatically shifts the fuel from one tank to the other to compensate for the weight distribution. When this happens the gas needle moves, sometime by a 1/4 of a tank. Maybe this is what you are seeing.
Race Director
Joined: May 2000
Posts: 14,542
Likes: 5
Originally Posted by army2000
You have two plactic gas tanks that sit behind the seats. The car automatically shifts the fuel from one tank to the other to compensate for the weight distribution. When this happens the gas needle moves, sometime by a 1/4 of a tank. Maybe this is what you are seeing.
Racer
Joined: Feb 2005
Posts: 267
Likes: 0
From: Banner Elk NC
St. Jude Donor '05
you may want to run some fuel cleaner such as TecTron through your fuel system. Also BG44K works well if it is a sensor problem. Also use good gas although gas is like gold now 
http://store.yahoo.com/wyattarpdodge/bgautprod.html
http://store.yahoo.com/wyattarpdodge/bgautprod.html
Safety Car
Joined: Feb 2004
Posts: 4,208
Likes: 2
From: Rochester MN
CI 5-6-7-8 Veteran
St. Jude Donor '04-'05-'06-'07
NCM Ambassador
Originally Posted by flash134
you may want to run some fuel cleaner such as TecTron through your fuel system. Also BG44K works well if it is a sensor problem. Also use good gas although gas is like gold now
http://store.yahoo.com/wyattarpdodge/bgautprod.html
http://store.yahoo.com/wyattarpdodge/bgautprod.html
, except that the additive is Techron (made by Chevron if I remember correctly). Sulfur content of gas varies by brand and the Vette sensors seem to be very sensitive to sulfur. I understand GM is about to release a newly revised version of the sensor to try to eliminate this problem. Try the fuel system cleaner first, if that doesn't work you may have to have your sensors replaced and/or have your PCM reflashed to the current level.
Instructor
Joined: Feb 2002
Posts: 220
Likes: 1
From: Pleasant Hill CA
Fuel Sender problems
Sounds like one of the fuel senders is acting up. As someone said, the vette's fuel measurement eqpt can act up with poor quality fuel and it has been prone to acting up with higher than normal sulfur content. When this happened to me the first couple of times, the fuel gauge would drop to 0 "LOW FUEL" would light up when my gauge was between 1/2 and 1/4 of a tank seconds before. I complained to the dealership when it was still under warranty and they replace 1 of the 2 fuel sensors......It happened again sometime later someone on the forum mentioned to throw some Techron in there and avoid cheapo gas stations and use Chevron gas. Ever since, I haven't had a problem yet.
Give it a shot....it's got to be cheaper than having someone dig through the whole fuel system.
Give it a shot....it's got to be cheaper than having someone dig through the whole fuel system.
Safety Car
Joined: Nov 2003
Posts: 4,979
Likes: 5
From: San Diego, CA "leaf" "tee" "e"
Originally Posted by army2000
You have two plactic gas tanks that sit behind the seats. The car automatically shifts the fuel from one tank to the other to compensate for the weight distribution. When this happens the gas needle moves, sometime by a 1/4 of a tank. Maybe this is what you are seeing.
There is a link in the C5 General Sticky to a thread with a very comprehensive explanation of the fuel system.
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Racer
Joined: Feb 2005
Posts: 267
Likes: 0
From: Banner Elk NC
St. Jude Donor '05
Originally Posted by ptdrummer54
, except that the additive is Techron (made by Chevron if I remember correctly). Sulfur content of gas varies by brand and the Vette sensors seem to be very sensitive to sulfur. I understand GM is about to release a newly revised version of the sensor to try to eliminate this problem. Try the fuel system cleaner first, if that doesn't work you may have to have your sensors replaced and/or have your PCM reflashed to the current level. Yea my spelling is not to good at 2am drinking VO and sprite 
It is Techron