Noisy Idle speed valve on a K4M

[ijaen]

Lately the engine (1.6 16v k4m) has developed a less than perfect idle, the speed is ok, between 750 and 800rpm with no aircon and a bit higher with the aircon engaged...changed all coil packs, new plugs, cleaned the tb, cleaned the CAS....nothing, the engine has slight misfire that is noticeable only without the aircon running...but yesterday I heard the idle speed valve (Magnetti Marelli one) make a rattling noise, disconnected it with the engine running and the noise stopped (and the idle didn't change a bit). The engine never stalls or idles high so I suppose the valve is working fine...but do they all make this rattling noise?

 

[Will.]

They don't have a smooth idle. I think it's due to the s**t engine and gearbox mounts. When I bought mine, the other 3 that I test drove all had this problem. Although I found it wasn't as bad when I had my prospeed exhaust on it. But maybe because I loved the noise it made.

 

[ijaen]

They don't have a smooth idle. I think it's due to the s**t engine and gearbox mounts. When I bought mine, the other 3 that I test drove all had this problem. Although I found it wasn't as bad when I had my prospeed exhaust on it. But maybe because I loved the noise it made.

Well, it had a perfectly smooth idle until a few weeks ago...maybe the mounts are not helping but the engine is definitely not running as smooth as it was and the noisy idle control valve is really weird...

 

[James23]

I thought the idle control valves were meant to make a noise?
when testing both of mine they make a sort of an agressive vibrating/wobbling kind of noise. Try using a tank of v-power (or whatever super unleaded you have there), from what i've read on here it's helped with peoples idles.