Volkswagen: 1998 VW golf Problem, auto electricians, lambda sensor

Question
Thanks for replying.  It's 16v.  Yes it is when i'm slowing down near junctions etc.  1998 S Reg 1.6S Mark IV.  Also just recently it has started to rev upto 30 on its own.  My garage has told me to take it to an auto electricians as he cannot find a fault.
Followup To
Question -
I have a problem with my 1.6S Mark iv 1998 VW Golf.  Whilst driving my cars cuts out with no warning lights showing.  The rev counter is never still and is always jumping.  Whilst driving the car also stutters. I have had the lambda sensor replaced and this has not made any difference.  2 different garages cannot find a fault.
Answer -
When the car cuts out, is it when you lift off the accelerator? ie. pulling up at junctions? Does it cut out while the accelerator is depressed? is it a 16v or 8v engine? One of the possible problems could be air leaks in the brake servo pipe, or a dirty / clogged throttle valve (may require removing and cleaning around the throttle valve, also the temperature sensor can cause cutting out problems and poor running. hope this helps and feel free to contact me with any answers to questions above.

Answer
you should get the garage to clean out the throttle valve, this should stop it cutting out. as for the reving upto 300 rpm, it sounds as if the throttle valve is malfunctioning. try cleaning it out before replacing it though. hope this helps. john dempsey