Sub par MPG's. Trying to get more

[deisenba]

After the first 3/4 mile it is 15 miles of flat driving at 65 mph. Should be good MPG's from that stretch. I wasn't very clear in the last post that the 3/4 miles at the start of the drive is to get to the highway. Downhill and flat after that with no stops.

Talyn apparently didn't know that running the defrost cycles the a/c compressor. He is receiving more education than he is giving.

 

[SuperRA]

Regardless of whether or not the AC is on or defrost is on, the AC clutch pulley is spinning 100% of the time the engine is on. So if you have a problem with that such as a bad bearing causing drag, it could be causing a slight decrease in power/mileage. Of course it depends on how bad the bearing is....

 

[CobraMarty]

Winter gas sucks for mileage. Lose 10% with it.
Driving 65 instead of 55 will lose 12%. 75 instead of 55 will lose 25%.

Use cruise control and slow down.

 

[Tony_SS]

Yep, winter gas.
Get the correct size tires and match the speedo gear to them.
Replace the cat.
Reset by unplugging the neg battery cable.

Those are your best bet.

My mileage sucks right now... 100 mile on a half tank. Unacceptable IMO.

 

[Jeepguy03]

Also you could put a programmer on your, being a 99. That doesn't solve whatever has it down, but will help it.

A programmer won't work on an XJ. A complete waste of money.

 

[old_man]

Run a can of BG44K through the gas to clean out the injectors and carbon. If you are strapped for $$ the Techron Chevron works and runs about $6 instead of $20+.

For a vehicle with over 100k, this is probably the best thing you can do for the buck.

 

[Keekleberrys]

I don't buy your friend getting 25mpg on 31's and 3.5"

 

[rockclimber]

he probably has his speedo uncorrected.

when I had 3.5" and 30"s my mileage was about 19 max. avg about 16

 

[Tony_SS]

I don't buy your friend getting 25mpg on 31's and 3.5"

Me either... too many folk brag about mileage like its some kind of piss contest. I don't buy half the claims.

 

[Digger87xj]

I'd be elated with 17

 

[Tony_SS]

I would be too. Hopefully when my engine breaks in and gets some miles on it, I'll see 17.