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why oh why does my car use so much fuel

Old 12-22-2005, 06:52 PM
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Default why oh why does my car use so much fuel

Ok yall, yet another mystery to crack, i fill up, car goes about 100 miles or so before empty, i just put some exhaust tips on last week and they were alloy one, the pig snout ones from GP GTs and GTPs, and they are black already, my granddad said something about it burning too much fuel, so i only drive to and from work about 4 miles each way, and maybe 30 miles a day total and i put 35 in it sunday and by wednesday i had to put 35 more in it cause it was almost outta gas, its not leaking anywhere under the car, we have checked, and the O2 sensor i know would cause bad mileage, but this bad? this is kinda ridiculous, i really like this car, but between this and the billions leaks i gotta try to find, SO, please help, and then we will move on to yet the next problem after that
Old 12-22-2005, 07:07 PM
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So your going through close to 20 gals in 100 miles. That'* only 5 or 6 mpg. Do the 92'* have a locking door for the gas cap?
Old 12-22-2005, 07:28 PM
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have you checked the Fuel pressure and the Fuel Filter?
Old 12-22-2005, 08:47 PM
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The O2 is the most likely cause. Clearly by the blackness of the new exhaust tips the motor is running very rich.

My suggestion would be to start with an O2 sensor. At the same time check your catalytic converter for rattling. Burning that much fuel over any real period of time will ruin the catalytic.
Old 12-23-2005, 10:25 AM
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Default 02

Yes prbably the 02.
What have you done for a tune up lately?
How old is the 02?
Old 12-23-2005, 11:41 AM
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O2 is unknown age. He just bought the car. Jeff, change it. And the plugs, as you've probably got them all fuel-fouled now.

And watch that cat as mentioned. Jeff, you should have a single wire (purple) non-heated O2. The cheapest one through the years. Get it ordered.
Old 12-23-2005, 01:00 PM
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From what other people have posted, as well as from personal experience, gas mileage will drop to about 12-14 when the O2 is shot. But then again, if your has been lazy/bad for long enough, your plugs and cat getting clogged up could be causing the greater drop.

It also doesn't help that you make so many short trips, especially with that unheated O2. It will take it longer to warm up, and getting the air fuel ratio where it should be.
Old 12-23-2005, 10:00 PM
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im gonna get one in the AM and will change it out and let yall know, the plugs are still fine, ichekced them this evening hopefully this will help some. Thanks alot for all the help and advice
Old 12-24-2005, 07:21 AM
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Default I had similar problem.

When I first purchased my 1993 SSEi, my fuel milage sucked :? Under the car when I would give it a lot of gas you could hear a woosh of air.....Clogged converter! :( So I replaced that and my 02 and milage got a lot better. BUT the the second biggest improvement I got with MPG and everyday driving is when I changed plugs to ac delco'* and started using better gas above 91 octane only. HUGE IMPROVEMENT! Yes premium gas is expensive but in an SSEi well worth it!
Old 12-24-2005, 01:27 PM
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Default mpg

My 96 drank fuel when I got it. Changed the 02 and plugs and now I can go 100 miles on a little over a 1/4 tank.
I also use a gas additive that turns 87 into premium burning fuel.
The gas corn additive is terrible out here.

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