Idle Problem Solved -- Just Sharing

[Ron A]

Recently, my 92 Classic had a problem where after driving awhile and
coming to a stop, the rpm would drop below idle, then would head for
zero. When it did that, it would keep doing it, which made it difficult
to drive in stop and go driving.

I took the tube that goes from the top right of the exhaust  manifold to
the bpt valve off. In the area where there is supposed to be a pin hole,
that whole area was filled with carbon. I used carburetor cleaner and a
dental pick to remove the coke-like material. There is a bolt in that
area. When I removed it, it was like the hole went nowhere. More cleaner
and it broke through the carbon.

Now it's all cleaned up for the next 200k miles and idling like it should.

If you decide to do this, I had to remove the air filter bellows tube to
the throttle body, one end of the vertical rod that goes to the throttle
plate (the fsm says to replace the rod if you remove it, fyi), the coil
to the distributor and the connector in that area, and all that black
can stuff at the front of the engine, the names of which escape me, so
you can get to the 24mm bolt at the manifold. By rotating and sliding
the tube, you can get it out. You have to remove the two bolts that hold
the tube in place also. First time takes about 2.5 hours. I could do it
in about half the time now, knowing what needs to come off.

Sometimes searching the archives returns too much material, so I just
thought I'd share.

Ron Atteberry
92 Classic