Idle speed, engine judder and start up revving

[i_am_fubar]

Borrowed the OH's MK4 (2001 estate, 1.6l petrol) this week while my motor was in the garage. Andddd.... I broke it. Or rather, a bunch of symptoms have started since I've been using it. Hoping you guys can help get me out the doghouse.

In the past it's had a rough idle of 600-800 which I'm inclined to put down to the throttle body needing a clean. On top of that, it now does the following:

- Revs up and down between 1000 and 2000 on start up without a foot on the gas. Stops as soon as you start driving.
- Judders/Caughs when at speed and the accelerator is released. Juddering stops about 5 seconds later.
- Idle is now at about 1200, yet the idle hunting seems to not be there.

My driving style, as I'm used to diesel, has a lot of harsh revving to avoid stalling and I am led to believe that the throttle 'learns' driving styles. Maybe that?

Reading around, it seems that coolant temp sensor or throttle body are probably to blame. Any advise from people more in the know?

Cheers

Sam

[ImIMK3]

Might want to look at a few things:
- spark plugs cracks or poor sparking
- MAF sensor disconnect and start the car see if this affects the idling
- throttle body needs a clean
- breather pipes for splits
- engine mounts for movement

Give it a go if it doesn't help then connect to a engine diagnostic for fault codes. Hope this helps.

[i_am_fubar]

Cheers MK.

Next question is how I get the d*mn engine cover off 

I'm lead to believe that following a TB clean, it needs to be re-aligned. Any idea how much this would cost for a garage to do?

Cheers,
Sam