hi
i have an 86 gxl that is only getting 10 - 11 mpg i am look for ways to increase that whether it is replaceing or checking certain parts

thanks

 

maybe you drive it too hard.



First you should worry about the engine's state of tune. Fuel mileage should be a distant second.



Get a manual and do everything in the maintenance section.

 

I have a thread on this as well, I feel your pain.

Searchh a tad, there was some suggestions on my thread that may help you.

 

First: Check compression

Second: Check TPS per FSM

Third: Check O2 sensor

Fourth: advance the timing

Fifth: Verify that the stock air intake is intact or that you have an actual cold air intake (not a cone filter under the hood.)

Sixth: Shift below 3,000 rpm and do not exceed 30% throttle.

Seventh: Hold the throttle at a stable position, do not pump it constantly as some do.

That is about all I have for you, the worst my car ever did on a tank was 17mpg, short tripping to the store and running two autoXs. You should be able to get over 20mpg on just about every tank.

Driving 75-85mph on the interstate, I can get 30 consistently.

 

I had the exact same problem as you. No one seems to listen to my advice but trust me.

Start with the thermostat. As soon as I replaced mine my mileage went from 11mpg to 15mpg. Before that I had changed the spark plugs, wires, O2 sensor, and air filter (K&N drop in filter which helped as well.)

Just recently I changed the ECT sensor behind the water pump which bumped my mileage up to 17-17.5.

It still pales in comparison to those getting 20-28mpg but 17 is much better than 11mpg. I coulda saved a LOT of money if I had just spent the 15 bucks and replaced the thermostat months ago.

Oh by the way my car is a 1991 N/A GXL with 145,000 miles.

 

Buy a Honda Civic. I hear they get great gas mileage.

 

If I was not stubborn I would have got a better gas mileage car but nah I had to get a 7

 

check sensors!! all of them, check for vaccum leaks!!! change fuel filter!!! new spark plugs, run the propper gas(87),check compression,never use anything stant! anyone who tells you different about stant deserves to be shot. make sure you have the proper injectors, change O2 sensor, check for clogged cats, verify you secondary ports are functioning, check grounds,talk nicely to ur car....you no give it a hug once and a while.....dont beat on it....the closer the pedal goes to the metal, the more gas you use. if i missed anything ill write it down later or someone will finish.

lastly the thing that will save you the most gas.....the search bar

 

i know why it gets such bad mileage!
because you bought a 7
duhh

 

Quoted for truth, except step 1.5 should be check to see if your catalytics are clogged.

 

How many miles per tank do you get and how big is your tank? What year is your car? What computer are you using?

 

15 gallon tank getting about 160 miles using a stock comperter (everthing is stock)

 

that only adds up to 10.6 . . . . typo?

 

You guys get great gas mileage! I got roughly 8-10mpg with bad compression, NO o2 sensor for about a week, huge exhaust leak, and running richer than milk chocolate!

 

He did say 10-11 mpg. That figure falls directly into that range.