SLK/R170: M111 Kompressor Engine Help Please
Thread Starter
Super Member
Joined: Jan 2006
Posts: 584
Likes: 1
From: Atlanta, GA
C230K
M111 Kompressor Engine Help Please
My C 230 Kompressor uses an M111 engine similar to the SLK 230, so I am hoping to find some help from this people in this group. Have any of you experience anything close to the folowing? Nobody have been able to help me solve this.
At startup and for the first few minutes of running, do you here a slight hissing or "pffft pffft pfft pffft" type sound when accerating normally. You don't hear it while you are idling. The engine has to be under moderate load like when accerating normally from a stop. It goes away fairly quickly as the engine warms up and then stays away until the car sits over night or for a very long time (all day). If I didn't know any better, I would think it was a crack in the exhaust manifold. The car has done this for years. First MB dealer could not fix the problem. Now a second dealer in another city also has tried but hasn't fixed it. This only happens to me in the morning and normally will not happen until the car sits and totally cools down for a long time. The extended warranty is about to run out and I would like to get this problem solved if it is not normal.
I just need some feedback to know whether this is normal for other M111 Kompressor owners (or not) so that when I go back into the mechanic I can feel confident telling him he really needs to research this a bit more.
Thanks in advance!
At startup and for the first few minutes of running, do you here a slight hissing or "pffft pffft pfft pffft" type sound when accerating normally. You don't hear it while you are idling. The engine has to be under moderate load like when accerating normally from a stop. It goes away fairly quickly as the engine warms up and then stays away until the car sits over night or for a very long time (all day). If I didn't know any better, I would think it was a crack in the exhaust manifold. The car has done this for years. First MB dealer could not fix the problem. Now a second dealer in another city also has tried but hasn't fixed it. This only happens to me in the morning and normally will not happen until the car sits and totally cools down for a long time. The extended warranty is about to run out and I would like to get this problem solved if it is not normal.
I just need some feedback to know whether this is normal for other M111 Kompressor owners (or not) so that when I go back into the mechanic I can feel confident telling him he really needs to research this a bit more.
Thanks in advance!
Thread Starter
Super Member
Joined: Jan 2006
Posts: 584
Likes: 1
From: Atlanta, GA
C230K
I should clarify and say that this sound is in addition to normal "roar" added at startup when the kompressor kicks in full-time during warm-up to compensate for the air pump found usually found on normally aspirated engines.
Thanks.
Thanks.
MBWorld Fanatic!
Joined: Nov 2001
Posts: 6,211
Likes: 2
From: Laguna Niguel, CA
The secondary air injection system is activated during warmup. It has a pump that makes sort of that sound and a leak in the tubing for that system maybe making the noise. You'll know when it's bad enough because you'll get a check engine light for a secondary air injection code. It is also possible you have an exhaust leak that goes away when the metal expands as it warms up. Get a mechanics stethascope and trace the source of your problem.
