throtlle switch

[weazgti]

Damn weather.Having a bit of a problem with my 8v digi, it hates the damp weather and the headlights being on.
The car starts fine and is set up fine but if i drive it in the rain or with the lights on its like the throttle isnt opening fully untill i get the revs up.It will do it in the morning but tends to clear up and drive fine but at night with the lights on it is constant,no full throttle,exhaust stinks really hot and idles high.However if i turn the lights off the idle drops down again.
Think the previous owner has had some problems because the engine bay has a lot of new cables and new earths routed and for some reason the wiring to the throttle switch has been cut and taped back on.
How can i check this is all ok,is there a certain voltage to the plug that i can check for?
What else should i check?

[rubjonny]

you should get 5v across the pins on the switch, and if you open the throttle just off idle and press the WOT switch on the top you should hear the revs drop, then pick back up again when released. that shows you tthat the wiring to the ecu is ok, then all you have to do is check the idle switch clicks when the throttle is closed.

once thats all sorted, checkfor air leaks, replace the ecu temp sensor with a new one from VW and set it up as per the digi tuning guide.  The black flying saucer on the rocker cover is a good one for vac leaks, the rubber bung it sits in likes to split.