Re: 2002 escape gas mileage
Fixing the emission control systems is always a good idea. How much fuel are you putting into that 16gal tank when you fill up? Check the PCV valve, it's only a few dollars to replace it and should be done every 60-80K. Buying a used vehicle makes one unsure about a lot of things - when it doubt, replace it before it causes you grief or leaves you on the side of the road.
If the engine light is on, get the codes scanned. Most of the time it's a small evap leak (fuel cap), or O2 sensor that has failed. Get a fuel pressure test done, make sure there are no leaks. "Highway driving" doesn't mean anything, other than constant moving with limited stopping. Constant cruise at 65 vs 75 can lead to as much as a 20% increase in fuel use.
As you bought this used I'll assume that you changed out all the fluids?
- engine oil
- transmission service (not a flush)
- transfer case fluid (ATF)
- axle gear oil
If not, old fluid will present drag/friction problems. The transfer case only holds about a quart of fluid, it should be checked periodically even between services for leaks. Going with synthetic fluids can add longevity to the vehicle and lower friction losses (like freeing up HP that is otherwise lost to friction!).
Tires are at proper pressure.
Vehicle isn't overloaded with unnecessary cargo.
Clean the throttle body.
If unsure of when the spark plugs were replaced, replace them.
Check air filter and replace as necessary.
If you didn't get any previous maintenance history with the purchase of the vehicle, you have some work to do.
'11 Ram Quad Cab 4x4 SXT 5.7L HEMI (stock); 48,500m
'06 Pontiac G6 GT 3.5L 220hp; 64,000m
'12 Chrysler 200 Limited 3.6L 283hp; 28,000m
'99 Taurus 3.0L 2V Vulcan 145hp; 154,300m - Traded
Amsoil in all vehicles!