High idle issue

[DCmk3]

Well I have ruled out the map sensor, they want £50 for the sensor, and they say it's more than likely not the sensor if there's no error codes from the sensor, and there are no error codes from the map sensor..

Rather lost now..

[Christo77]

If you can rule it out as you seem to have done then that's a bit more progress, a good thing no less!
Stick with it, it may be something simple..
I take it there's no mods on the engine.. or was it running right sometime before.. what has been done to it since then etc..
Your fault code reader, is it a professional diagnostic tool..

[DCmk3]

The engine is completely stock, it has been running like this since I purchased the car a month or two ago.
I did a full service on the car, including a new distributor cap and rotor also, replaced the timing belt and tensioner.
The timing has been set and I can't find any error codes with Vag-Com yet the high idle is still there.
I have removed the throttle body and cleaned it, closed it back up and ran a Throttle body calibration via Vag-Com.

I just cant figure out where the gremlin is hiding..

[Len]

1000rpm is high for idle anyway, should be around 850

Have you checked all the vacuum hoses and crank breathers?

[DCmk3]

I thought even 1000 was too high, what vacuum lines are there other than the one to the brake booster and the thin one from the FPR..   
When you say crank breathers, are you talking about the one next to the oil filter on the block which joins to the inlet pipe?
Or are there more?

[Len]

I was speaking in general terms because I dont know your engine in detail.
The main vacuum hose to check is the one up to the ECU.
On my 16v I had problems with secondary ones but they will probably be different to yours.
So any thin tube check it!

Yes thats the main one from the crank. Again I have others.

[DCmk3]

Alright ill take a look at the lines, it's just odd and rather annoying.
The crank breathers, I have cleaned those out recently.

[javalin]

I suspect your timing is wrong - you don't use a timing light (aka dynamic timing) on the 1.8 or 2l  mk3's - its all done statically by lining up crank/cam for machanical and the dizzy for the ignition timing.

Read this site, look at the diagram about 1/2 way down on the right.

http://faculty.ccp.edu/faculty/dreed/Campingart/jettatech/t-belt/index.htm

Don't use the crank cog, but use the flywheel reference by looking down the gearbox hole.

James

[DCmk3]

The timing was lined up by the flywheel and cam when I changed the belt.. 

[Christo77]

Have a think about what javalin said.. your plugs kinda indicate a timing problem too..
Not a guarantee that it's defo the answer but has to warrant a double check through eh.
Keep at it..