'87 5ktq--no idle

[Mike Veglia]

I guess my old faithful '87 5ktq got a tinge of jealousy from the "Pearl
Beluga" ('95 A6q Avant) that started parking next to it last Sunday. That,
and sharing my commute miles with the 4kq for the past few months perhaps.

Anyway, last night on the way home from work (in heavy stop-and-go freeway
traffic) the 5ktq was suddenly not idling--at all. Kinda a pain to heel-toe
it home, but not that big a deal. Being busy last night I "fixed" the
problem by driving the 4kq to work today (that'll teach it to act up on
"it's week"). I have done next to no troubleshooting yet, but here are some
observations:

1. The engine was running perfectly--just no idle. Good (normal) boost,
smooth, easy to hold 800RPM with the throttle. Because of this I'm
suspecting it is not due to a serious vacuum leak that would usually have
drivability problems associated too.

2. After getting home I shut it off to switch parking spots (put the 5ktq
into the "storage spot" and the 4kq into the "daily use" spot in the
carport). Upon restarting all was back to normal (good idle). Strange, but
due to time constraints...it gets the "parked" punishment anyway ;-)

3. I did briefly pop the hood. While idling away as if there were nothing
wrong I disconnected the ISV cable--it died immediately, same as in the
failure mode. Upon reconnecting the plug into the ISV the idle did not
return without shutting down and restarting (hmm, sounds like Windows).

So, based on the above my initial theory is bad electrical connection at the
ISV plug, or bad ISV, or WOT Switch, or ????? I was thinking about a
Pick-N-Pull run this Sunday anyway, perhaps I'll get lucky and find a
suitable substitute ISV there cheap to try.

Meanwhile...thoughts and suggestions will be greatly appreciated. I will dig
in and do some proper troubleshooting this weekend. Right after helping my
wife wax her new car's Pearl paint ;-)

Mike Veglia
Motor Sport Visions Photography
http://www.motorsportvisions.com