I know the EPA spec says 17/24 city hwy.

But in reality I get 11.5 to 12 in the city and 13.8 hwy.

Is this about right? Or should I be looking at something?

tia

 

Ant:
Thats a little low. I dog mine and get at least a couple mpg better. Have you looked at your LTFT ? Any CEL or codes?

 

Wow, that's pretty low....
I get an average of 17mpg in the city, and on a recent 160 mile trip, I reset the odometer, and got a 23.3mpg at a average 75mph of highway driving... Whenever I get high octane gas in Texas (93), I get even better mileage of ~24.5mpg...
Your mpg's are way low....

 

ant17
Your mileage is way way low. Are you dragging an anchor or stuck in second gear? Something is not right!

 

Have a go at cleaning your throttle body inlet around the butterfly. Next undo the two screws holding the MAF in and disconnect it from the engine loom.

Squirt some electrical contact cleaner in there and clean the sensors, there's 3, one you can obviously see and two up a channel. Once you've done that clean out the part load breather. These three things, along with a hard reset could assist mpg.

If you get stuck have a look in the sticky's in both this forum and the xk8/r forum on how to go about the above, there's pictorals to help you along, it shouldn't take long to do these little jobs, and you should see better averages.

 

Sean,

Thanks will do. Found it.

 

Cleaned everything well, just measured the old fashioned way and I'm getting 12.5 around town.

Shouldn't it be better than that?

What else can I check?

thanks

 

Air filter. It can make a big difference in gas mileage, and of course, tire pressure - seriously.

 

You should be doing better than that on mileage. See if you can make sure your torque converter clutch is locking up in the two highest gears. TCC not locking will kill mileage.

Cheers,

 

Can I check that, or do I need a trans shop to do it?

 

relating to the torque convertir..what are your RPMs at 70 MPh..should be about 2400 if it is much higher than it is probably your torque converter..

 

No, you can do it. When you are at a level speed of 50 MPH, the TCC should be engaged. Watch your tachometer as you LIGHTLY push the throttle to slowly accelerate. If you see the tach needle respond immediately to your foot and blip upward, the TCC is not locked. Once you get the feel of this, you can always tell whether the TCC is locked or not. When you crowd the throttle like that, the RPM should not respond immediately to your foot if the engine is locked to the wheels like it should be. By the same token, once you accelerate hard enough, the TCC will disengage anyway for more torque, and you will obviously see that on the tach.

Give that a whirl.

 

Thanks All, will try both!

 

Tried the 50 mph thing in a local forest preserve, the tach increased but very slight increase. More testing with longer road needed.

 

If the tach blips faster than the speedo at that time, you are not locking up. Do it a few more times, you'll get a feel for it.

Cheers,