Extreme idle hunting, help!

[Barnsey8008]

Idle hunting goes crazy if idle is set below 1500rpm, and then randomly goes off when the car is warm and the fan kicks in. I have noticed the revs drop substantially when brakes/lights/fan are on rather than raise, the idle up adjustment doesn't seem to make any difference. I have replaced all vaccum lines, tried every damn idle adjustment and it looks like the previous owner has also been trying to fix it. Not sure if it the autochoke or what, has anyone had this issue? Or know a good diagnosis?

[James]

Hey man. You have something not sealing your idle air off properly. Autochoke or throttle body mechanical stop are the first places I would look. In good condition, at operating temp. The only thing bypassing the throttle bodies should be the brass screw in the auto choke, that is the idle adjustment screw.

[Barnsey8008]

Cheers man ill have a look into this

[KingCity]

It does sound like the idle screw is set to high but also check the rocker cover breather hose on the cambelt end as they tend to split roughly half way between the throttle body & rocker cover, you can tell if they are split as they leak small amounts of oil around the hose.