Weird High Idle Situation

[tgmuneer]

Hi all

Need some advice on my 1984 M20B20 L-Jetronic unit.

In all occasions, the engine is smooth with no misfire or hesitation. Power is good.

1. Single crank start when cold and idles at 1000rpm

2. Idles down to 800rpm when warm. However it jumps to 1,500rpms after driving it.

This is where it gets weird...

3. I switch on the air conditioner and it clicks down back to 800rpms. Stays that way even when I switch off the air conditioner.

4. Jumps back to 1,500rpms after another run.

Any ideas? Cheers!