Check gauges light when at 1/4 of a tank (plus just generally way off)
09-26-2005, 10:25 PM
#1
Check gauges light when at 1/4 of a tank (plus just generally way off) My check gauges light comes on when I get under a quarter of a tank...and here is the kicker..if the guage is right then Im only getting the gas mileage of a supercharged Hummer with 4.10s. 
After a complete fill up, I got about 260 miles before the gauge started reading damn near on E...and this is a 99 M6 SS so I have the 16.8 gallon tank and had been driving conservatively with plenty of 1-3-5 shifts. I had been driving maybe a good 45-50 miles in the city on the E when the car ran out of gas(thankfully near a friends house) Do I need a new sending unit? If so, how much do these usually run? Thanks for any help.
After a complete fill up, I got about 260 miles before the gauge started reading damn near on E...and this is a 99 M6 SS so I have the 16.8 gallon tank and had been driving conservatively with plenty of 1-3-5 shifts. I had been driving maybe a good 45-50 miles in the city on the E when the car ran out of gas(thankfully near a friends house) Do I need a new sending unit? If so, how much do these usually run? Thanks for any help. 
09-27-2005, 07:54 AM
#3
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Figure out what mpg you're getting. The gauges in these cars can vary widely from car to car. For example, the Firehawk will set the check gauges light right before it gets on E...we can go another 50 miles or so, and still only have to put in ~14 gallons. In the WS6 though, I've had the gauge on E, not set off the check gauges light, and only had to put in ~12 gallons.
Remember too, that depending on where your gas level is in the tank, sometimes your gauge is going to move faster or slower (the tank isn't evenly shaped the whole way down from what I've been told/read.) My gauge can sit on full for awhile, move really quickly between 3/4 and 1/4 of a tank, and then slow down again after 1/4 of a tank.
Just estimating the number of gallons needed after driving 260 miles...sounds about right for the mileage. I know with city driving, the firehawk gets 20-22 ish typically. (It's an M6) But on straight highway it can crank out 29mpg. The WS6 usually does 18-20mpg in traffic (but it's an A4 with a high stall convertor).
Remember too, that depending on where your gas level is in the tank, sometimes your gauge is going to move faster or slower (the tank isn't evenly shaped the whole way down from what I've been told/read.) My gauge can sit on full for awhile, move really quickly between 3/4 and 1/4 of a tank, and then slow down again after 1/4 of a tank.
Just estimating the number of gallons needed after driving 260 miles...sounds about right for the mileage. I know with city driving, the firehawk gets 20-22 ish typically. (It's an M6) But on straight highway it can crank out 29mpg. The WS6 usually does 18-20mpg in traffic (but it's an A4 with a high stall convertor).
09-29-2005, 07:30 AM
#6
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When I hit the check gauges light I have roughly 3.5 Gallons of gas left in the car. Seems pretty typical to me. Maybe GM is trying to keep some of the procrastinators from getting stranded.
My SRT did the same. It had a 12 gallon tank, and at the low fuel light I would fill up and only have to put in 9 gallons.
My SRT did the same. It had a 12 gallon tank, and at the low fuel light I would fill up and only have to put in 9 gallons.
09-29-2005, 11:22 PM
#7
my understanding with the reasoning behind why we stay at full forever and than can seem to eat up a tank in 2 days is the shape of the tank... kinda like this V as the level goes down your consumption doesn't... there is more volume at the top than at the bottom... there for it takes you longer to go through the fuel up top than down below... but as it starts to deplete the level drops quicker and quicker and so does your gauge.
