5ktq stalls with CC on

[Doyt W. Echelberger]

My 87 5ktq engine has taken to stalling when I am running the air 
conditioner and letting up on the accelerator. Doesn't do this if I switch 
off the climate control prior to slowing down.

OK, this is what helps: I switch off the CC whenever I expect to stop at a 
sign or a light.  And I backed off the throttle screw a few turns, which 
brought the RPMs up to 800 with CC set at AUTO. Now sometimes I can stop at 
a light with CC on AUTO and not stall.

I suspect the deceleration valve, and/or the relay that speeds up the RPMs 
when the CC is ON.  But I don't know where these items are located or how 
to test them. My Bentley shows them in diagrams, but really getting to them 
is another matter. Car runs good otherwise.

All replies appreciated.   Doyt Echelberger