M113 knock sound, not sure what causes this
Thread Starter
Junior Member
Joined: Sep 2021
Posts: 34
Likes: 0
E350 4matic
M113 knock sound, not sure what causes this
Hello!
I’m kinda worried about knocking while accelerating.
I have M113 engine, 2006, 69K mi currently.
I can’t hear same sound when I put gear on P or N. No knocking when I revving, only hearable under D acceleration. Hearable between 1300-2000 RPM, and it is hard to hear from over 2500rpm or 40mph because of road noise.
Oil changed in stealership this month.
No idea whats going on.
heres two video,
One is knocking and one is idle sound.
Knock:
Idle:
Any idea where should I check?
Valve cover gasket and breather case is leaking but Im not sure this caused this sound.
I’m kinda worried about knocking while accelerating.
I have M113 engine, 2006, 69K mi currently.
I can’t hear same sound when I put gear on P or N. No knocking when I revving, only hearable under D acceleration. Hearable between 1300-2000 RPM, and it is hard to hear from over 2500rpm or 40mph because of road noise.
Oil changed in stealership this month.
No idea whats going on.
heres two video,
One is knocking and one is idle sound.
Knock:
Idle:
Any idea where should I check?
Valve cover gasket and breather case is leaking but Im not sure this caused this sound.
Member
Joined: Feb 2017
Posts: 248
Likes: 36
From: L.A., Moscow, NYC, San Diego, Baja
1998 E320 Wagon, 2003 W211 E500, 2003 W211 E500, 1999 W210 E55 AMG
I don't hear a pronounced knock, but I would consider checking the serpentine belt, idler and other pulleys to cut down the front end noise. Scan to check there isn't a misfire. Also, sometimes faculty motor mounts can contribute to what feels like a misfire.
Thread Starter
Junior Member
Joined: Sep 2021
Posts: 34
Likes: 0
E350 4matic
Thank you for the answer! If you turn up volume to max, you can hear something is hitting when rpm goes up. Mounts are checked, luckily they are still stable!
