Well, ladies and gentlemen, once again I come to this well of knowledge for
help with my erratic idle problem in my 85 Westy 1.9 L.

I continue to operate on the premise that the idle hunting and bucking is
the result of something I did (or didn't do) when I removed the right head.
I have checked all the hoses and the intake ports, adjusted the idle switch,
and renewed the gaskets on the exhaust collector joint.

Symptoms:  When I first start the engine (on a cold morning), it will idle
at very high rpm (I'm guessing 2000-2500 -- I don't have a tach) for around
3 minutes, then the idle drops to almost nothing, comes up to 7 or 800 rpm,
and drops off again.  This idle pattern then persists for as long as I run
the engine... dropping to probably 100 rpm or less, and coming up to 7 or
800, then dropping off again.

Question 1:  Can anyone suggest what I might be overlooking?  (Again,
assuming that the problem was caused by something I did when I removed the
right head to repair a head gasket leak.)

Another issue...

I mentioned previously on this board that my fuel economy has dropped since
the head repair.  (This may be related to the above problem.)  Prior to the
repair, the van had been running with the O2 sensor disconnected.  I
reconnected it after I did the head gasket job.   I measured the output
today and found that it never rises above .2 V.  I understand this could
tell the ECU that the engine is running lean and cause more gas to be fed
into the engine, resulting in the poor mileage.  Well, I disconnected it
again, and I'll see what effect that has.

Question 2:  What do you think the ECU is doing to the mixture with that O2
sensor input floating, i.e., not connected to anything?

Bottom line:  The van was running great and I was getting 19-21 mpg until I
got in there and started messing with it.  Isn't it reasonable to believe
that various components and sensors are still in the same state they were in
before the head repair and that I did something with the hoses and/or
injectors on the right head that messed something up?

Thanks in advance for your help.

Dave in KC
85 Westy