Re: 4KQ inconsistent rpm

[Huw Powell <human@nh.ultranet.com>]

> 1.  The car idles at about 1K rpm but sometime after some city
> driving, it revs at near 2K.

two things easy to check out first - the secondary throttle may be
sticking open, you can check that with the hood up, just operate the
thing manually (even with the engine off) and see if the secondary
returns properly.  second, their is a hose setup that looks like it's
part of the vacuum system.  It bypasses the throttle through an
electrical switch which should be at the front pass. side of the engine
compartment.  The switch closes when the AC is on, and lets extra air
into the engine - ie it raises the idle a bit to make up for the AC load.

I'm sure their are some more complex FI related possible causes but
they're a bit beyond me most of the time!

> 2.  When I have the heat on, the center vents blow cold air while two
> side vents blow warm air.  Any reason for this?

It's a feature, not a bug.  Why I don't know, it's a big pain in the
butt.  All spring and fall I had to open and shut the center vents every
day (want fresh while warm out, not while cold at night).  So when I
replaced my dashboard I customised it for warm air in the center.  If I
want fresh I'll open the windows or just turn the heat valve off.  Anyway
it's only hot here in New England for four or five minutes in July or
August so who cares?

PS I wrote up the process I used to change over the center vents, anyone
wants I can email it.  Warning: you will have to remove the dashboard.
It is a one day project though.

huw