Car idle's at about 550 rpm, does that seem right for a 05 Sti UK, seems too low as nearly stalls,
What is correct idle speed, and is there any way to fix it, -clean the icv or replace?
Car is showing no fault coded,

Thanks

 

Do you run a VTA chumpvalve?

 

No chump valve lol
Car is standard ppp sti

 

Good man. Look at idle control valve, and maybe maf. Does the issue stop once warmed up or is it there all the time? Throttle position sensor?

 

half way ish between the 0 and 1 on the rev counter there is a line. It should idle just about on this line. although its half way between 0 and 1 its not 500 its around 750/800. is the idle pretty smooth?

 

That sounds ok then, as it sits on that middle line, yes idle is smooth, but take a few seconds to settle,

Have just thought , only had this problem since I change battery, does dissconecting battery reset ecu?