On this '91 Sentra E I have, ratings say I should get 29-39 mpg on it. I am getting around 20-23. What am I doing wrong? I've tried to drive conservatively, shifting into neutral when possible, any tips? What can I do to get better mileage, upgrades, etc. And please include prices. I've also heard that more expensive gas (Chevron) will get you better mileage, is this true (how much better)? Thanks

no higher octane is not true. check for a basic tune up(spark plugs, oil, oil filter, distributor, and wires for corrosion) for upgrades there is a thread out called make sticky by fugiot...

http://www.automotiveforums.com/vbulletin/showthread.php?t=480607

theres the thread for upgrades

Wow, thank you for that thread. SO much useful info. And I didn't mean higher octane, standard unleaded. One place charges $2.43, while the Chevron across the street charges $2.63 for the same octane.

price in gas doesn't really matter...i guess it all depends on your location and what kind of gas they give you...ie i can tell what gas station gives me good gas by driving with it, but another gas station same octane, my car seems a little sluggish. its all up to what your car responds to

research your gas and find the one with fewest detergents added..... i use gate or shell when possible and mine comes out ok