The first time I had problems with my fuel gages, I had just had my 2003 vette about three weeks. I was driving on a 125 mile trip, and my fuel was getting low, but I kept going taking my gas gage needle way down into the empty zone. My goal was to get about 1/3 of the way on my trip to an area that always has the lowest gas prices in South Carolina. I made it there and filled the car up with high test. No problem until I was returning and the gas gage was slightly below the halfway mark and then boom I got the check gages light and noticed the gas gage was on E. Well I thought I might had a fuel leak so I stopped at the first available gas station (BP) checked for leaks and filled it up(8 gallons). This repeated twice and I jumped onto the forum and found out about Techron. I added 2 large bottles (this damn stuff is expensive). This did not help so after a short while I added Seafoam. About the only thing I noticed was that the gas gage started going to zero about the 2/3rds fuel mark. This was of course the wrong direction. Then about a week ago the gas gage seemed to start working right. So I decided to watch it. I had already started using my trip odometer as a back up and would normally refuel at the 180 to 200 mile mark. this time I decided to go with the gage since it seemed to be working right. Yesterday after not driving the car for a couple of days I left the house and about a block away I thought I noticed a miss in the engine. Sure enought another block later and going up a slight hill she stopped and was out of gas. The trip odometer was on 259 miles and the fuel gage (which seemed to be constantly moving in the proper direction as I burned my gas) still showed around 1/4 tank. My wife brought me a gallon of gas from the house that had 2 cycle oil in it and once I got the Vett on level ground, the engine roared to life. So off I go to the gas station now thinking great now the gase gage is working better but still ain't properly doing it's job. What a crock! Then when I get to the station (on level ground) it only takes 12.9 gallons to fill it up. So now I am wondering about the entire gas tank system. I am totally confussed. Can anybody put up a diagram of the tank/tanks configuration? Also can you remove the Gages and the pick ups with out dropping the tanks. If the answer is no, then how much trouble is it to drop the tanks. And when are we all going to get together and kick GM in the butt until they fix this problem.

High sulpher fuel????/ I don't have this trouble on any other car I own (5 in all).

Bill

 

worked for me

 

Bill, I'm no expert on the fuel system and others may chime up but a few thoughts

I have never run cars low on fuel and the one time I did recently I hit a gas gauge problem too. The simple answer would be that running low may have introduced dirt into the injectors and may have compounded the original gauge error. In other words two separate problems. Take a look at this post I made recently. Just a few of my thoughts on low contents

http://forums.corvetteforum.com/c5-g...h-a-twist.html

Taking each issue in turn

The sensors which feed the gauge become pitted because of high sulfur in the gas. Chevron uses Techron so it tends to clean the system as it goes. If you catch it early a Techron shot can cure it but I suspect many leave it until the sensor is too far gone for cleaner to work and thats when you probably need a sensor change. In your case you may be at that point. Its possible to DIY a sensor change without dropping the tanks. I'll see if I can find a link and post it up. New sensors will almost certainly fix the gauge issue although there is a firmware fix that others have had done which may help.

Onto the latest problem. At 1/4 full and only taking 12.9 gallons the car should not have stopped. Not sure I'd have added 2 stroke laced gas as that contains excess oil and may affect the injectors (not sure how much though). It may be that dirt in the system caused the cough and that it cleared to get you going again. A good clean again with Seafoam would be a good idea. Is there any other sign of rough running or any engine codes? But that may not be the problem although the alternatives get more complex and expensive.

The fuel system is a double tank with a cross feed pipe. The tank capacity is 18 gallons or there abouts. A pump in the right tank feeds into the left which feeds the engine.

Some members have had problems with the feed pumps. Try this post from Miker which describes similar problems and his efforts to fix it:

http://forums.corvetteforum.com/c5-t...post1571514483

Here's some info from my archive which describes a similar issue with Forum member Keppler's car and in his case it was a feed issue fixed by the dealer:

Thought I would share the repair information of the common C5 fuel gauge problem I've had for the past 2 years (2002 vert).

Description from the repair order: Fuel gauge goes empty when it has 1/2 tank fuel showing. When filling back up sometimes gauge reads full. Customer has run out of fuel with 3/8 tank showing. Customer has noticed vehicle has 18.5 gallon tank and has run out of fuel showing 14 gallons used when refilled.

Pull TSBS Doc #1411305 fuel system diag. Test fuel pressure. Test for fuel bleed down OK. Check scan data for both sending units. Test by draining fuel from rail and watching for sending unit voltage change. LH sender changes, right does not. Check for proper fuel transfer to jet pump in right tank. Fuel coming from left sender blow out metal transfer line to check for blockage. Check for fuel at inlet for RH fuel sender. Fuel to jet pump but no fuel transfer. Needs sender unit and jet pump. Replace RH sender unit and jet pump. Scan data for senders, vehicle fuel system operates normally after repair.

Parts: 89047748 Module KI 3.107 RH fuel sender assembly $480.00

Labor 3.5 hours
Computer scan $120


Hope that helps.

 

Thanks for the information. This at least gives me somthing to go on. I doubt 50 to 1 gas would hurt anything. I know the .8 gallons I put in more than likely helped the injectors. It got very diluted about 10 minutes after I got the car started.

I went to the mountains this week end and used my trip OD to monitor my fuel. after about 175 miles on what started out as a full tank, I found a gas station, but had a hard time geting any fuel in the tank. I finally got about 7 gallons in. Now this may have been a defective hose nozzel as I started having the problem at 1 gallon. The gage had dropped to zero once on the way up but after I stopped for about an hour and then it rebounded to about 6/10ths of a tank. This happend a couple more times after I put additional fuel in.

We stopped at a resturant with a helluva view and had dinner, while the sun set on the Blue Ridge. When I started to leave the entire electrical system went blank. No power! I was about to panic when the power came back on. Then I drove about 140 miles with no problem. Stopped at my daugters house about a block from my house and got the zero powr again. Long story short I got out and found that the negative terminal on a new battery was slightly loose. I moved it and off we went. When I got to the house I got out my wrenches and corrected this problem. Now I am wondering if this may have triggered all my gage problems (I should get so lucky!). The jet pump you mentioned also makes me wonder. Any additional posts you can give me would be appreciated. This is a very unsettling problem.

Thanks

Bill

 

I wonder if a bit of e85 to a mix of gas would help out :?

 

I had the problem with my vette and Seafoam straightened it out, had the same problem last year with my F-350 diesel and it fixed that also.