ECS failure
Thread Starter
Super Member
Joined: Dec 2007
Posts: 648
Likes: 1
From: Seattle
C-300, XC70, Wrangler
ECS failure
CEL came on during my afternoon commute on Tuesday. Looked it up in the manual and the book says "take it to the nearest MB dealer for service." Didn't have time just then, so waited for my evening commute (odd day, having 3 commutes).
Pulled in at just after 6:00 and they took the car. It was treated yesterday (Wednesday) as an "emergency" service.
Found that the ECS failed, and it was replaced. No charge.
So, what is an Exhaust Cam Sensor, and why is it important? Was this just an emissions issue, or potentially more serious. The dealer says that there's no damage to the car, so that's good.
(Car has almost 21K on it, and is 15 months since purchase.)
Pulled in at just after 6:00 and they took the car. It was treated yesterday (Wednesday) as an "emergency" service.
Found that the ECS failed, and it was replaced. No charge.
So, what is an Exhaust Cam Sensor, and why is it important? Was this just an emissions issue, or potentially more serious. The dealer says that there's no damage to the car, so that's good.
(Car has almost 21K on it, and is 15 months since purchase.)
Senior Member
Joined: Jan 2008
Posts: 373
Likes: 33
From: Vancouver, BC
08 C300
i believe (correct me if i'm wrong), that ECS sits right before the CAT.
it works with intake cam sensor to find out whether the car is running lean or rich, and adjusts to air/fuel mixture.
having said that, you should be fine. it's just sensor that acting up.
it works with intake cam sensor to find out whether the car is running lean or rich, and adjusts to air/fuel mixture.
having said that, you should be fine. it's just sensor that acting up.
MBWorld Fanatic!
Joined: Jan 2008
Posts: 2,424
Likes: 3
From: Ohio
X3 and 2012 C coming soon
The sensor was probably bad. There may be more to it, but the simple answer is: The ECS detects where the cam is in it's rotation so the computer can adjust the fuel injection timing according to when each valve is opening.
Edit: White46 got it out 2 min before I did.
Edit: White46 got it out 2 min before I did.
Thread Starter
Super Member
Joined: Dec 2007
Posts: 648
Likes: 1
From: Seattle
C-300, XC70, Wrangler
Update on status:
Car is home (I had a delay in picking it up). But, this is the interesting part, it sat overnight before it was serviced, and when they started it up, the CEL did not come on. They had to run codes to find that it had been on, and that led to the ECS. Good job!
So, if your CEL mysteriously comes on then off, you probably ought not to "trust it," but rather take the car into the shop.
Car is home (I had a delay in picking it up). But, this is the interesting part, it sat overnight before it was serviced, and when they started it up, the CEL did not come on. They had to run codes to find that it had been on, and that led to the ECS. Good job!
So, if your CEL mysteriously comes on then off, you probably ought not to "trust it," but rather take the car into the shop.
