MG zt 1.8 turbo rough idle problem

[mikesmgzt215]

Having a problem with my idle, when I start the engine the idle goes between 700 and 900 rpm constantly going up and down. If I leave the car running within about two minutes the revs drop off and it trys to stall then revs up to counter act the drop, does this a few times then goes back to idling between 700 and 900 again. If instead of leaving the car running I drive away it still try to drop off the revs when driving,so two mins or so into your trip at about 15 or 20 mph you get a sudden drop in power for a second like a sudden stamp on the breaks then it's fine like nothing happened. It's like it needs to clear it's throte. Anyone got any ideas? Could this be idle controle vave?

Edited by mikesmgzt215 on Wednesday 8th July 22:32