Mileage...

[Dracalous]

Ok, I've fixed the coolant leak that was fogging up my windows, replaced the stereo (no antenna, though), fixed my vacuum and idle problems, and replaced teh air filter.

Now I need to know how to improve gas mileage. I know it should be better, but I'm not sure how to fix it.

[ubermich]

When's the last time you replaced the spark plugs/wires and rotor?
And check your timing.

[SteveTheFolkie]

what kind of mileage are you getting? I'd check for ....


1) proper inflation
2) no dragging brakes (especially the if you've got front e-brakes ....)
3) clean air filter
4) good, well gapped plugs
5) good quality plug wires
6) new high quality cap and rotors
7) correct timing

Of course, how you drive has more of an impact than any of the above - if you've always got that boost needle shoved over to the right you're gonna suck a lot more gas down than if you keep the boost level low.

I've got an '85 NA 2DR Hatch - drive 120 miles round trip every day as a commute (mixed highway / surface street) - last fillup I got 34 MPG - typically I'll get 31-33 - from what I understand my mileage is exceptional - if I knew the secret I'd tell ya'all ...

Of course, that Thule rack (seems to be the most common brand on Saabs around here) on the roof looks neat - but it'll cut into your mileage pretty seriously - especially if you've always got your mountain bike up there - just in case ....

Steve

[Matthew]

Also check the NTC sensor, AMM and O2 sensor. Those contribute towards fuelling measurements.

What fuel economy do you get from the car at the moment? We really need to know to judge whether it's consumption is excessive or not.

[SteveTheFolkie]

Originally Posted by Dracalous

Not entirely sure. I can go almost two weeks on one tank. My odometer stopped working either before i bought it or after I replaced the left drive axel and CV joint.

time is meaningless for determining fuel consumption - I drive 120 miles a day - five days a week - so I burn a tank of gas in three days - see what I mean?

To calculate mileage we need to know how many miles you travel on a number of gallons of gas - for example - if you travel 120 miles on 10 gallons of gas, you're getting 12MPG - rather pathetic - if you're going 330 miles on 10 gallons of gas - you're getting 33MPG - quite good -

Steve

[Jim Mesthene]

You need to check the Lambda duty cycle/pulse ratio.
Within a small range, the Lambda system controls the mixture. You need to know if you're in that range. If not, you are surely burning too much gas.
A crude starting point is to find out if the modulator valve on the left inner fender is buzzing.

[Dracalous]

Originally Posted by Matthew

What fuel economy do you get from the car at the moment? We really need to know to judge whether it's consumption is excessive or not.

Not entirely sure. I can go almost two weeks on one tank. My odometer stopped working either before i bought it or after I replaced the left drive axel and CV joint.

[Jezzadee]

I get 4 days to the half tank, except at weekends.

[grif900]

there is a simillar discussion going on in another thread (auto trans question).