Hey Scotty i have a rough idle when the water's temp is in the middle(normal operating temp). The thing is, the car works fine on the road. The revs dip when i stop in a light then goes back up and back down on it's own. The throttle body is fine, has been checked and cleaned.
The Jimney was sold in the U.S. as the Samurai. All we have ready access to is information for U.S. models.
The reason idling improves when you turn on the AC is probably due to the "A/C Idle Up valve" noted in the online manual for that vehicle. Probably a good thing to do would be to check for vacuum leaks seeing as how hoses and gaskets are 36 years old if original. You might also check spark plugs for signs of excess wear or abnormal combustion. The link below is the repair manual for the U.S. specification 1990 Samurai with 1.3 SOHC engine.
Also no Check Engine, no missfires or anything. Just that. The problem seems to go away temporarily when i use the ac.