Gas Gauge=Possible Dummy Gauge?

[CTOESHO]

Does anyone else have issues with their gas gauge? For example, on my way to Performance Plus (100 miles), I got exceptional MPG according to the gas gauge. At the end of the 100 mile trip (give or take a few), I was just under the top line in F (full). On my way back from Performance Plus, which was roughly another 100 miles, I was riding between a 1/2 a tank to a 1/4 of a tank. I couldn't believe that I had 5/8 of a tank left. So I got home and drove into Chicago, and by the time I hit 250-260 miles, I was finally exactly at 1/2 a tank. By the time I got to where I was going, and finally drove home, I had driven a total of 320 miles. The problem is, is that I'm at a 1/4 of a tank now. How come I could travel around 260 miles on the first half a tank, but only 70-80 miles on a 1/4 of a tank on the second half of the tank? Is my gas gauge a dummy gauge? I know the second half goes a lot quicker than the first, but not by this much. Sorry for the long post.

Mike
93mtx

 

[WaterRooster]

I know what you mean. I can normally pull 150 miles on the 1st 1/4, then the last 1/4 I get about 50-75. Now that I know it, I just deal with it.

Shawn

 

[fredhurderjr]

It's like that on many cars (especially the older GMs...)

The shape of the float handle, shape of the tank, etc. have a lot to do with it. My Monte would stay at full forever, then plummet.

Also, if your fuel pump has ever been replaced, the float may have been bent a little. That'll screw up the readings.

 

[megaplay]

Trust me it could be alot worse. My car before this was an 87 Olds. After a half tank the needle would float anywhere between empty and 3/4 of a tank and you could watch it in full motion. Just keep an eye on you trip meter for about how many miles you can get.

 

[sdpatt]

The fuel gauges on most cars have a great deal of conservatism and very little precision. The travel of the needle is not linearly related with the change of level in the tank. The markings on the gauge should be very close together at the top of the range (1/2 tank should be about 3/4 of the way up the scale) and farther apart at the bottom. There is usually a reserve capacity designed into the E indication to protect those individuals that think they can make it on fumes. The "LOW FUEL" light comes on with about 5 gallons remaining in my tank. With an 18.6 gallon tank, that is over a fourth of the tank volume. Not really "low" fuel is it?

You really have to try to bend the float arm on the level sender. I did bend it to try to get it to be less pessimistic about how low the fuel level was and it wasn't something you could do accidentally.


------------------
Scott

1991, 254K miles, glass hood, police grill, SVO shifter, Catz fogs,
K&N, 73mm MAF, Superchip, PP Y-pipe, Borla cat-back, 190 lph pump
Eibach/Tokico/polyurethane, SHO Shop front & rear strut braces,
16x7.5" Moda R1, 225/55ZR16 Bridgestone RE730, -1 deg camber x 4,
Class II hitch, Silver award at the SHOklahoma Car Show

[This message has been edited by sdpatt (edited 01-12-2002).]

 

[CTOESHO]

How fast do you guys drive on the highway? On my way to Performance Plus, I averaged between 75-80 mph. In order to get the best MPG, at what speeds should I drive? Thanks.

Mike
93mtx

 

[bigsho]

To get the best MPG drive at a low RPM or don't drive it.