Celica 190 year 2000 revving up by itself

[jcmr2]

Know a guy has a 2000 celica 190, it will sit at 1000 rpm for a while and then it will suddenly rev to 2000 revs for no reason and stay there for a while then it will drop back down. Any ideas

[TotalControl]

IIRC it may be the Idle Control Unit.

[jcmr2]

They tried that but it dident work.

[gavzdc5445]

IAC Valve? happened on my old impreza, that was fault, took it to diagnostic and was bang on.

Maybe take off and clean with cotton bud and brake cleaner?? If lots of black gunk round it, wipe it clean which should resolve it, even temporarily if IAC Valve is knackered.

[jcmr2]

What is an iac valve?

[gavzdc5445]

Idle Air Control Valve (IACV). I know Subarus are prone to this, never heard of celicas having issues though. But from the symptoms you have described, sounds the most likely cause of Revs Jumping or rising

[gavzdc5445]

check this link- describes in a small bit of detail which may be of use:

http://wiki.seloc.org/a/Idle_Air_Control_Valve

[jcmr2]

Thanks, i will tell him to look into it.

[TotalControl]

gavzdc5445 said:

Idle Air Control Valve (IACV).

Thats what I bloody meant!

Stupid me.

Edited by TotalControl on Friday 20th November 22:38

[gavzdc5445]

So how did your pal get on? was it an IACV right enough?

[jcmr2]

He tried that but it dident work. My pal is a mechanic that was looking at it he has since give up on it and told your man to take it away.