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Bad Gas Mileage driving me nuts!

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Old 03-02-2004, 08:50 PM
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Default Gas mileage.

My 96 K motor only gets 15 - 16 around town and 25 highway.
28 highway in the summer.
It must be the nature of the beast as I've tried all the obvious things to get better
city mileage and nothing seems to improve it.
I like my C motor at least I can tweak the TPS voltage. It gets good mileage (around 20).
Old 03-02-2004, 11:55 PM
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thats bad?????????? i got 21 highway....in the fall...
Old 03-03-2004, 02:33 PM
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Nowhere in this entire thread do I see anyone mention checking the tire pressures. A loss of 2-3 mpg is easily attributable to low tire pressure, and you lose a pound for every 10°F drop in temperature in the winter months, so get those tires back up to 35 psi or so, and you should feel an immediate difference in handling and rolling resistance.
Old 03-03-2004, 03:13 PM
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Default Mileage

My 90 SSE got bad mileage when I got it. After I went through the car it got
a little better (16-17) city.
The main culprit was the front brake calipers causing drag and increased
wheel rolling resistance. This really effected city driving but didn't seem to
bother the highway numbers.
It wasn't until I did a front brake job I found that the lower caliper bolt slides (each side) were seized. This was causing the caliper not to release properly.
I had to remove the rubber bushings and file out the debris with a round
file in the casting .Then I installed new bushings with a coating of high temp RTV on each sealing end so no more water could get into the caliper casting.
The mileage then went up to 20 mpg city. No problems since.
Just something else you should consider.
Havent done my 96 front brakes yet. I'm told its a different design.
Old 03-04-2004, 11:53 AM
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actually its not the tire pressure. I check the tire pressure every week and mounted and balanced the tires myself. There are absolutely no leaks and the pressure is holding at 35psi.
Old 03-04-2004, 12:02 PM
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Pulling off an aftermarket intake will kill milage. On the phone with Ol' blue eyes, he moved his metal pipe from his 94, to his new 99 SSEi, and the 94 lost about 5 mpg.
Old 03-04-2004, 02:06 PM
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It won't stay that way The PCM has to relearn. Then it'll be ok. He won't get it all back, but most of it. A good breathing intake will get you an additional one or MAYBE two mpg.
Old 03-04-2004, 07:03 PM
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i took that intake off cuz i was getting sick of the way it looked in there. I need a new rubber coupler for the two pipes because the one i have now is starting to crack. Anyone know where i can get a good rubber coupler?
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