larsianer

could this be the chain tensioner,that is making this sound??
i have tryed without the serpentine belt, and the sound is still there
its a w211 220cdi 2008,with 430,000km

larsianer

i have now changed the chain tensioner,and the sound is still there, i also have tryed without the serpentine belt, and the sound still is there, am waiting for the harmonic balancer belt drive wheel..what you think??

Tschuss_Bill

I hear a bit of metallic rattling. Is that the sound? How old is the belt running gear? Have you tried an automotive stethoscope? Does turning the AC have any impact? Does it vary with engine speed?

larsianer

thank you for reply,i have tryed without the belt, and the sound is still there,the strange thing,is that its more sound, if i turn on the heating inside the car, what is the belt running gear??

Tschuss_Bill

By running gear I meant the belt, pulleys etc. On some models there are bushings that wear on the air box that can cause a rattling sound.

More sound with the heat turned on? Is that the case with heat on and AC is in off position?

larsianer

yepp thats the strange thing....and the idle fluktuates also...but like i said, the sound is still there,when i try without the belt/serpentine

samaritrey

Did you check for chain stretch?

larsianer

No,how do i check the chain for strech??
what do i need to remove??