In the last three days, the Vana-gremlins have been hard at work:

Developed a slow leak in the right front tire. Saturday morning went to
the tire repair shop. Small nail removed, hole plugged, went on my way.
Drove directly to my son's tint shop. Customer coming out as I was going
in, stopped me, said "Hey, did you know you have a nail in your left
front tire??" Turned around, and sure enouh there it was, actually a
screw, in the left front tire. Went straight away to the tire repair
shop and had it fixed.

While waiting in the customer lineup for the tire repair, I decided to
check my engine compartment, as I was still having s slight twitching
during when driving. Wiggled the air filter housing and noticed movement
in the crankcase breather hose which connects to the big air hose
connected to the AFM. Closer inspection disclosed the hose was totally
disintegrated in the center. So whatever crankcase pressure/vacuum that
was supposed to be there wasn't. Had to hunt down a hose piece at the
FLAPS and effect a repair. Low and behold, FLAPS  "GAVE" me the 8" hose
piece I needed!! Mucho T'anks.

In the process of the hose replacement, I discovered the big AFM hose
didn't want to stay connected to the AFM. Realized the clamp holding it
was not wide enough to get a good grip on the AFM hose port. Went in to
the parts house and bought new but wider clamp, now hose stays tightly
connected. Drove a bit, twitch still there.

Stopped, checked the engine again. Spotted a vacuum hose disconnected.
Re-fitted and drove on. Still a twitch.

Goint on home, stopped at a light, engine rpm dropped down to normal
idle of 850, 900 rpm, then suddenly began to rise and didn't stop until
reaching 2200 rpm. I thought " this is nuts", Then the rpm dropped about
300 to 1900 then rose again to 2200. I drove it on home.

At home I immediately disconnected the ISV, then drove it. No Change..,
idle, then sudden rise to 2200 rpm. I adjusted the idle by 50 rpm, still
no change ... 2200 rpm, reconnected the ISV, no change, still rises to
2200 rpm. Disconnected the voltage side of the O2 sensor, NaDa, no
change, 2200 rpm. Checked for sticking linkage. All worked smoothly.

Now I am at a loss on this. I have made a thorough check of all the
connectors and vacuum lines. I have not started with a meter yet to look
at voltages, but will soon.

Does any listmember have any experience with this high rpm syndrome. I
had a similar thing sometime ago, but a simple idle speed adjustment
took care of the problem. Nothing seems to work in this case. I have
been reading my DigiFant FI system shop manual, but have not found any
answers.

Any input on what may be causing this and/or how to trouble shoot would
be appreciated.

John Rodgers
88 GL dRiver