My 960 runs well and all but seems like she likes here fuel a little to much. While I don't drive like granny, I am not doing burnouts or driving over aggressive. Mostly city driving but I'm getting a little over 100 miles per half tank. What gives?

 

When was the last time the car was tuned up>

 

I have no clue since i just bought it. What are your thoughts on a tune up on this engine? So far I have only replaced the air filter and flame trap.

 

I don't understand the question.

What year is it? I'd start by getting the real gas mileage. A few of those cars made the "cash for clunkers" list. I once got 548 miles on one tank and didn't run out. I was getting about 25 mpg around town. Fill up, rest the odo, drive till it's down to 1/4 tank, fill up again and run the numbers.

I after I got the true mileage I would go to work, starting with the plugs. Only use Volvo OEM single tip plugs. Do you have a CEL?

 

It's a 1995 960. Other then spark plugs what would you think might be the culprit for poor gas mileage?

 

I'm not even sure you are getting poor gas mileage. Are you pumping 91+?

 

Yes, premium fuel all the time. I have a 20 gallon tank, that means I should get at least 200 miles with 1/2 tank for the 20 mpg (even that is poor I think for a 6 cylinder).

 

Well, you can't always depend on a 18 year old fuel gauge. Lucky the thing moves at all.

Still didn't say if it has a CEL?

I use to own a '95.

 

How does it idle? Is it smooth or rough? A rough idle could be a vacuum leak=poor gas mileage. Check your lines for leaks, they probably will be brittle. I'm a recent owner of a '97 960 with 240,000 miles on it and I'm still learning the car. Other than plugs and a air filter, there is not much to a tune up, you already have covered the flame trap. There are no wires or cap to worry about.
I'm getting around 19 mpg mixed driving and I haven't changed the plugs yet but there next on the list.

 

No CEL and yes I do have a vacuum leak for sure. I need to look into that just waiting for warmer days (no garage)

 

I'm getting 15 mpg after testing.

 

Change out the plugs and find & correct the vacuum leak. Is it going into OD? What does the tach say at 55? Mine says 2000 when in OD going down the road. Any chance you have a stuck or hung up caliper?