ML 350 CDi idle speed

[JuneG]

Hi,
I have an 11 registered ML 350CDi, bought from main dealer just over a month ago. I've noticed it idles at different speeds. Nothing to do with engine being cold or warm. When the engine is warm sometimes it idles at around 7 and sometimes around 9.

What should the 'normal' idle be? Is this a problem that needs fixing?

Thanks.

 

[Steve@Avantgarde]

Idle should be between 750 and 900rpm so its in the range. When the engine is at idle there are lots of sensors taking and adjusting values depending on what kind of run you have just done, for example the quantity control and EGR valves, MAF sensors etc.

It may be normal, but worth a fault code check on STAR nonetheless.