sticking throttle

[e30-320i]

my car has devloped a problem over the last few days now and again when i take my foot off the pedal the revs stay in the same place and when i push the clutch down they start to climb.i now know its not the cable as i pulled up at work at lunch time and it was idleing fine i popped the bonnet and as i walked toward the front of the car the revs started to rise(never started to rise on its own before).the tb butterfly must be closing as i can hear the tps click the only thing i can think of is the tps is knackered does anyone have any ideas or know if the tps is the same for 320i/325i as i still have my old 320i tb in the shed

[Templ8e30]

Could well be a dodgy throttle switch, they are indeed the same part for both 320i/325i.

Cheers,

Iain T