I average about 20-21 on mixed driving (50/50 city/freeway) and about 16-17 for city only and hard driving. I have seen as high as 24 MPG on highway driving.

Big keys for better gas mileage are:

Sparkplugs and wires (the factory NGK spark plugs last at the most about 10-15K miles- the wires no more than 30K miles, usually closer to 20K miles).

Oil (using the wrong weight for the temperature will reduce your mileage- as well as quality… oil should be changed every 5K miles at the most (3K miles on a Turbo))

O2 sensor (if it has more than 50-60K it is time to replace it)

And air filter and gas filters. Again the stock ones are only good for 10-15K miles.

Remember my mileage is on a slighty ported non-turbo FC with CDI ignition and Iridium spark plugs.

 

actually O2 sensors are used on less than 1/3 throttle in most cases, so highway driving and idling are where you'll see the biggest gains in gas mileage when a new one is used.

 

Damn, you guys need to get your stuff checked out. My 87 n/a, pretty much fully modded and streetported, got around 18mpg mixed driving, and 20+ on the highway. This is with sporadic spirited driving.

My AE with a 60-1 turbo, mild port, 720s and 1600s gets around 16 with mixed driving. Gets lower fast though with spirited driving.

 

I figured I might share my mileage from my last roadtrip. The one listed as ~100mph includes "spirited" 140 sprints , no worries. Nothing sucks gas like that though.. damn

 

Awesome, just happening to be installing a new one tonight infact. I'm not sure it will help much, but every bit helps.

 

Where is the O2 sensor located? Throttle body?

 

Exhaust manifold.

 

Bosch makes a direct plug & play O2 sensor for our cars- no need to splice anything, 'bout $27, if I remember correctly...I posted the p/n for it about 3 months ago on this site...

 

do you even have a cat.

 

negative here.

 

i got about 11.5 miles per gallon

 

Hey Dude, this is what I've done. I got about 12 - 14 mpg before changing out the factory air box. Now I get around 15 - 17 mpg. Today I'm changing the fuel filter, spark plugs, plug wires, and O2 sensor if I can get it loose. I try to shift around 2200 rpm, this seems to help too. My goal is 20mpg but I think it takes a tottaly different driving style in addition to the tune-up. Good luck in your quest for better MPG

 

Most peoples problems I bet. I wouldnt be suprised if someone said "wow there is a gas filter?"

 

i get around 20mpg with mine but i stay on top of the mantiance with it - it has headers, intake, exhaust and pullies and a few other goodies

 

Bone stock with 3 original cats, I get 22-23 mpg on the highway, 17-18 mpg in town. Keep the spark plugs and fuel system clean and save money.

 

A malfunctioning TPS will cause awful gas mileage, so I would test and adjust that first.

 

wow..i have a Turbo II Convertible and the most I use is 17mpg...I used to use local gas(at over $5.60 a gallon) Then I started driving smart and I got a little over 20 a gallon on city/highway mix. Make sure tires are inflated and check every time you get gas, coast as much as you can..use that cruise control as much as possible and stay at 2500rpm in 5th gear...make sure everything is up to par(fuel filter, plugs, air flter,etc) When it is hot, use AC and keep windows up...don't shift too low in a 7(at least 3 grand))oh...coasting-make sure you leave it in gear...now I don't care as much as before as I gas up on the base now and that is less than half price

 

full tune up, fuel filter air filter etc

 

Running LT-8 ECU, factory internal port configuration, complete 89+ intake manifolds (ported), emissionLESS, 5th-6th sleeves removed, VDI constant open, RB header/pre-scilencer, Borla cat-back, custom COLD air intake.

Getting 19-20 MPG highway and about 15-16 city

Regards,
-Markus

 

i did mine yesterday after a auto X and i got 22.6 MPG. but ima gona change the fuel filter, spark plug and wires. my car starts horrable some times so i hope the wires an pluges help that too. i have a ported intake , air filter(crappy 1) and muffler shop exhast. and a coulpe of NOZ stickers........j/k

 

i know i'm running rich w/ my walbro and intake/exhaust setup w/o proper tuning. even w/ new plugs, new filter, new o2 sensor and new plug wires...i ONLY get about 13 mpg mixed but mostly hwy. one tank i actually got 17mpg! i was jumping for joy at the gas station! lol!

-jet-

 

I get around 14 in the city
20-23 highway depends on how often I break 100mph.

 

well i was having a problem with my gas mileage and i checked the codes and i kept getting one long light and then 2 short lights. well it was the pressure sensor code. so i didn't know how to fix it so i went ahead and got a new 02 sensor and then plugs and oil change and i got all the way up to 11mpg from 10mpg. well just diggin around my engine bay and i say that the connector for my pressure sensor wasn't on there so i found it and then i am getting like 20mpg and that is with alot of drifting on the weekends. so i would do all of the above and then just check to see how your pressure sensor is connected.

 

Wow...you guys with low MPG's need to have your cars checked out. My N/A gets a full 24 MPG highway with a little punching it here and there. My TII needs a new O2 sensor wire, so its sucking down gas...but that car is still a work in progress.

-Joe

 

25 to 26 before the rebuild, something around 28 now(1300 miles after rebuild), most of my driving (90%) is highway, averaging 75-80 mph...