gas mileage...Y the change?

Bigme574

Registered User
I get a median of 17-19 MPG...If I drive with boost or without. What can I do on this 89 sc to increase gas mileage? I put in new O2 sensors, cam sensor, crank sensor...and all EGR compnents. What else is there? Will the DIS help me...should I drop 85 bucks on that?

Thanks for looking
Aaron
 
If you are talkin' 17 to 19 in stop and go city driving, that's about right. My (former) SC would get in that neighborhood in city driving, and about 26 on the road if i drove it sanely around 75 mph or so.....for a year I commuted 80 miles a day over a mountain pass (on I 90 though) and i usually drove 90+ unless it was rainy or icy, and i averaged 23 driving like that.

If you are only getting 17-19 on the highway at a moderate speed, then i'd check normal tune up stuff ( plugs, wires, air filter, vacuum leaks). Don't think DIS could cause bad mileage, they usually either work or don't, but many parts stores can test them for you and give you a printout of each circuits performance. I don't think you can buy a new one for $85 though, I think it's more like $175. I fyou DO need a DIS I have a known good one (tested at NAPA with the test results printed out) that I'll sell for a reasonable price, but I don't think you need one.
 
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i doubt if dis would help if its running ok , maybe new plugs or wires , if it pings premium gas would advance the timing more . maybe warmer thermostat like 192 degrees , i get around 20 around town and 31 hiway with colder plugs and 180 thermostat running regular gas with good exhaust , my eec tuner helped about 2 mpg till it quit , if you keep boost under 4 pounds it stays in closed loop which helps , check the air in the tires may help, i have 2.73 rear end gears that helps too its only like 1600 rpm at 60mph
 
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plugs

plugs and wires are new...double platinum, 180T-stat...tires at 36psi each. no vac leaks...tested with air compressor. K&N air filter, all synthetic oils. The DIS at autozone was 85 bucks 2 or so months ago...now its up to 129.00...but may get mine checked....never got over 24.5...straight hwy.

thanks for the replies...ill figure something out...perhaps i have 3.27's? havent checked that yet..but everything else is stock
 
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