Doesn't engine friction generally decrease (until the tail-end of the engine's 
life anyway) as time goes on? The mileage on our Jetta has gone up 1-2 mph 
gradually in the nearly 4 years that we've owned it.

-Erik

In message <9504181456.AA26962@lenti.med.umn.edu>  writes:
> On Tue, 18 Apr 95 09:45:29 CDT Marcus Doherr said:
> >This has been discussed thoroughly last fall. Here's my experience:
> >1980 Vanagon with Pop top, 2.0l F.I., Man. Trans., no extras
> > -> 15-17 mpg on short trips
> > -> up to 22 or 23 mpg on long highway runs (60-65 mph)
> 
> well, see, i'm getting a little worried about my bus. the mpg has been going
> UP for the last 16,000 miles. to such an extent that the AVERAGE for 86,000
> miles has risen 0.2 mpg. now, to me, that's a lot (for the long term average)
> ... and it worries me. for years, it plodded along at 19.4 average. now it's
> creeped up to 19.6 and gives every indication of going to 19.7 this summer.
> 
> yeah, i know: don't look a gift horse in the mouth. but this bothers me,
> if it was going down, then i'd know something was wrong and i'd had some
> ideas. but this! i don't think i'm driving that much slower. i don't think
> i'm driving any less in town. the ONLY thing i can connect to this is that i
> started using those Bosch triple-electrode plugs just about the time the mpg
> started going up a little. ??? coincidence?? maybe the plugs just suit my
> driving style better? maybe the old plugs were that much wrong??
> maybe they've done something to the gasoline around here? maybe my bus is
> really a Democrat?? ;)
> 
> arrrrrrrrrrrrrrrrggggggggggggggghhhhhhhhhhh!!!! old folks hate change!! :)
> 
> anyway, i'm getting up to 21-22 on the highway now. and 17-18 in town.
> 
> subject to change without notice.

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