Hi, I recently got a gl 10 turbo wagon, and am getting around 16 mpg on freeway driving. Yeah it's got an a/t and 202k miles but I thought it should do better than that. Any ideas what I should do? Thanks.

Check timing, O2 sensor, air filter, brakes adjusted too tight, leaking fuel

Hi, I recently got a gl 10 turbo wagon, and am getting around 16 mpg on freeway driving. Yeah it's got an a/t and 202k miles but I thought it should do better than that. Any ideas what I should do? Thanks.

 

I had bad mileage for a while - turned out to be a vacuum line. though mine is a carb not FI. Good luck.

change the oxygen sensor it costs less than $30 dollars and takes 5min on a turbo it's the wire coming out of the down pipe that will help allot i got 8mpg when i did mine

Stay out of the turbo for one. When the system goes into boost, the AFR goes through the roof. Under boost it's common to tune at around 10.5:1 AFR. N/A engines can run upwards of 17:1 or higher at cruise, and even at peak HP an N/A will still be running around 12.5:1

 

Sadly on an auto, this means you need to drive *very carefully* at 55 MPH. Anything above that and you are in positive manifold pressure (boost) at all times. It's the gearing of the 3 speed automatic that's to blame for this. Realistically, 20 MPG would be decent with a turbo *and* an auto tranny. Change it for a 5 speed and you'll get an instant 5 MPG.

 

Basically, the EA82T can get about 24 or 25 MPG if you really baby it (with a 5 speed). But if you drive like grandma in order to get 25, then you might as well not have the turbo at all, and just get the full 30 you would have without it.

 

02 can help - and clean the MAF. The MAF, TPS, and 02 are the biggest culprits of poor mileage.

 

Also make sure the exhaust is TIGHT. Any leaks forward of the 02 will introduce fresh oxygen and send the ECU a lean signal which will dump MORE fuel in. Any car with an 02 should have a very tight exhaust for best mileage.

 

GD

I should have mentioned that my driving is pretty gramdma-ish. It does have some ticking, I don't know if that effects mileage. I notice with that a/t at 65 mph it's running at about 3500 rpm. It's like it needs another gear. I can see where a 5 sp would do better.

 

Probably a dumb question but what's a MAF and a TPS?

 

Thanks for the advice!

Ticking won't hurt your mileage - but you should definately consider new oil pump seals.

 

MAF = Mass Airflow Sensor.

TPS = Throttle Position Sensor.

 

TPS you just test and make sure it's working as it should.

MAF can be cleaned with some brake cleaner.

 

GD

my 88 turbo a/t gets 23-24 mpg ,hi -city mix driving , mine seems to run better on higher octine , but mpg is the same , if you can take the big fat cat off , 2in pipe all the way back , + everything else said before

I'll just throw in that you also probably want to go ahead and replace your fuel filter and PVC valve. I'm pretty sure the PVC valve took my turbo Legacy from around 18 mpg up to 22 mpg in city driving.

I'll just throw in that you also probably want to go ahead and replace your fuel filter and PVC valve. I'm pretty sure the PVC valve took my turbo Legacy from around 18 mpg up to 22 mpg in city driving.

 

They have valves made of white plastic piping? :lol:

PCV is what you meant...sorry i dont mean offense i just couldnt resist.

Having finally purchaced an 88 GL10 Turbo last spring because I wanted more power I expected it to get something similar in gas mileage as the rest of my subes ( 24-30 ) but it only made 17 at the best. Most of the rest of my subes have 3 spd auto and the 88 has a 4 spd. I found that the intermediate band in the trans was misadjusted. I adjusted it to factory specs and low and behold 26 mpg hiway 22 around town. It is something to check because it also made my trans shift a lot better.

They have valves made of white plastic piping? :lol:

PCV is what you meant...sorry i dont mean offense i just couldnt resist.

Doh! I usually run it through my head... Positive-Crankcase-Ventilation.

Changing my 02 sensor gave me a few extra MPG's on my turbo.