M104 engine running on
Thread Starter
MBWorld Fanatic!
Joined: Feb 2011
Posts: 1,752
Likes: 175
From: London, UK
W212 - E63 AMG
M104 engine running on
Hi guys, anybody experienced their M104 engine running on after the ignition has been turned off?
I bought mine with this issue, thinking it would hopefully go away when I do the necessary upper engine wiring loom replacement, but sadly it's still doing it.
Any ideas?
I bought mine with this issue, thinking it would hopefully go away when I do the necessary upper engine wiring loom replacement, but sadly it's still doing it.
Any ideas?
Super Member
Joined: Jan 2015
Posts: 920
Likes: 46
From: Worcestershire UK
W124 260E
You will need to remove the connector in the alternator, thats after you switch off the ignition in the car .If it runs on ,then you have another problem. But this will rule out the alternator .A faulty alternator can cause this . Only remove the plastic connector ,and not the brass one .. Another thing is if the car was jump started in the past it can damage the ECU ..
Thread Starter
MBWorld Fanatic!
Joined: Feb 2011
Posts: 1,752
Likes: 175
From: London, UK
W212 - E63 AMG
Thank you sir, that's useful. I remember my mechanic telling me a while back that the alternator was grumbling like it needed a change soon. I think I'll remove it and get it tested/reconditioned. Fingers crossed this solves it. I'd hate for it to be something like pre-ignition after the engine is turned off.
Thread Starter
MBWorld Fanatic!
Joined: Feb 2011
Posts: 1,752
Likes: 175
From: London, UK
W212 - E63 AMG
Thanks Optimus 
I'll give it a try when I get home tomorrow (away for xmas break right now).
The thing is, the running on, is usually for a few seconds, so it's going to be tricky to navigate my arm all the way down there (if it can even fit) to take off the connector. I'll give it a shot though. Any advice is definitely appreciated. I need to solve this mystery and my hood mystery before I invest any more money into the car.
I'll give it a try when I get home tomorrow (away for xmas break right now).
The thing is, the running on, is usually for a few seconds, so it's going to be tricky to navigate my arm all the way down there (if it can even fit) to take off the connector. I'll give it a shot though. Any advice is definitely appreciated. I need to solve this mystery and my hood mystery before I invest any more money into the car.
