revs hunting on tick over

[clancy]

Last few months my cars seems to rev it's self on tick over, not every time but pretty often. Jumps up to about 2k then back to tick over revs

Any ideas on cause ? Air box mod has been done and it's an abf engine if that's relevant

Any help appreciated

[GOLF-MK3-GTI]

Clean throttle body and then realign using the following procedure;


Disconnect battery for a few hours best overnight then reconnect both terminals. Then turn on the ignition, don't start the engine though and don't touch the pedals. Leave on for 30 seconds then turn ignition off and then start the car straight away not touching any pedals. That should align the throttle body.

[clancy]

Will give that a go thanks for the idea

[gasketface]

Air or vacuum leak ? .Faulty ISV ?

[LR5V]

Air or vacuum leak ? .Faulty ISV ?

ABF? it will very likely be the above