Strange idling problem 172

[bollis]

Hello all, got a problem, have done a search, but couldnt find any answers. As of today my 172 has starting idling between 1000rpm and 2500rpm, its revving itself.

Also the temp gauge is going all the way to the top, straight back to the bottom and then bounces around like a rev counter. The problem is from cold and stays there for the whole journey, just done a 150 mile round trip and was waiting for it to die on me!

Anybody got any ideas?

 

[telford_mike]

the idling thing sounds like a throttle potentiometer (seen the same thing on a Dynamique)

Back to the dealer I think!

 

[bollis]

Yeah its looking that way, its going in on Wednesday for a new gearbox too. Only problem is I was supposed to be going to York on Tuesday, thats a 600 mile round trip, dont think so now!

 

[JAY172]

the high rpm is a defect setting used by the computer if a sensor goes into open circuit. most likely a potentiometer fault but that doesnt explain the weird readings from the temp gauge. maybe there is a wiring problem. best let your dealer have a look eh.