Saw a full page ad in this morning's paper for some stuff you add to
your oil.  Claims a 10% to 21% increase in gas mileage.  Car magazines
used to call this stuff mouse milk, but haven't seen much for years
(anyone remember Wynn's Friction Proofing).   Amazing what people will
fall for.

Sigh. We're drinking Miller Lites now instead of Corona Extras - half the
price, but only about half the buzz, too.

My '91 EB 4x4, 200K got an engine rebuild about four months ago. It had some
teething problems - lousy mileage, check engine light on, and so forth. He
finally "cleaned the injectors" and that seemed to do the trick - no check
engine light and the best mileage I've ever gotten (20 mpg mixed) for a
couple of months.

Took it back in last month for some front end work. He popped the hood to
listen to the engine (it still had a bit of lifter noise) and noticed a
vacuum line was off - I think it was to the defroster or something like
that. He plugged it back in, I left (having made an appointment for the
front end work) - and was most annoyed to see the return of the check engine
light and have my mileage plunge back to 13 or so.

After much scratching of heads, the mechanic finally concluded that my
catalytic converter was a bit stopped up, which was causing the O2 sensor to
trigger the check engine light (and the computer to keep the engine running
full rich - thus the lousy mileage). However, the unintended vacuum leak
apparently counteracted that and kept the engine running a bit on the lean
side instead!

I don't have a new catalytic converter yet and at the $400 quote for
replacement parts and labor it may get 'converted' into a straight pipe.
However, I did pull that vacuum line back out, and now it's running fine and
getting 20 mpg with no check engine light. I'm told that replacing the
clogged cat with a straight pipe will also encourage the engine to run lean,
so I can plug that vac line back in and have good mileage AND a working
defroster...what do you think?