Question to the forum: My '04 S has an erratic idle that varies up and down by approx. 30 RPMs. It's throwing no codes and runs just fine. Mods can be seen in my signature. Could this be a exhaust valve problem (possibly sticking)? I've owned the MINI for around 2.5 years and it has not received a walnut blast during that time. It doesn't really affect anything except my sensibilities. Anyone else run into a similar issue? Thanks.

 

I'm pretty sure my R50's idle has never been super stable, but I've never checked how much it varies. Why would you walnut blast it? It's a port injection motor.

 

I've never done it but my understanding is that blasting removes carbon buildup on the back of the valves and prevents them from seating properly.

 

That's typically not an issue with port injection; the gas washes the intake valves off. It's also not usually a problem on exhaust valves (well, not on the backs of the valves, at least).

 

Ac on or off?

 

AC off.

 

I’d say it’s normal.

are you seeing the fluctuations in inpa? The needle on tack hardly moves +- 30

Idle is a constant calculation based on readings from multiple sensors…it will naturally fluctuate

 

I had similar issues and tried to have the tuner smooth it out. In the end he put the idle into open loop Va closed loop and it smoothed out perfectly.

 

I’m 100% stock engine. I’ll monitor my idle and report back

 

Checked mine

was seeing 730’s -760’s…

could not hear or see the fluctuations on the tack needle