I recently purchased a 1999 XC70 with 140k miles on it. It seems to be in great shape and my local volvo guy gave it a clean bill of health on all the surface and obvious issues.

However, we're hovering around 17 or 18 mpg average and we do not believe that is optimal for a 2.4L engine.

The tires are properly inflated (if not a hair over-inflated) and I changed out the fuel filter last week.

My two questions:

1) Is there a list of things to replace for this kind of fuel economy? On order of simplest/cheapest to most complex/expensive, what would you check/replace first?


2) Does anyone know of chip tuning not for performance, but for fuel economy? Is there a simple conversion package for veggie oil for this model?


Thanks for your time.