INJECTOR PROBLEM
Thread Starter
Newbie
Joined: Feb 2024
Posts: 3
Likes: 2
W212 2010
INJECTOR PROBLEM
Hello, does anyone know or have any suggestions on how to solve an issue with one of the injectors on a W212? I’ve already added Liqui Moly injector cleaning additives to the tank three times, but the problem still persists. I’ve visited several mechanics, and each of them has said it’s likely one of the injectors, possibly over-injecting fuel. There's a slight knocking sound when the car accelerates, approximately between 2000 and 3000 RPM. Additionally, the car experiences certain vibrations, but only in third gear – at 3000 RPM, it shakes and vibrates heavily. When I shift to a higher gear, the vibrations stop, likely because the engine isn’t as loaded and isn’t over-injecting fuel into the cylinders.
Mercedes Benz E200 W212 2010. (DELPHI injectors)
Mercedes Benz E200 W212 2010. (DELPHI injectors)
Out Of Control!!
Joined: Apr 2019
Posts: 11,923
Likes: 6,776
From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
UNKNOWNS...
How do you know it's an injector... ?
What engine type is this?
What fuel pressures ?
what idle fuel trims: LTFT
Have you switched them around ?
What cylinder do you suspect is acting up?
Is your VVT working right?
Any other "unrelated" chassis faults ?
Have you rebooted chassis??
What's the current mileage?
What engine type is this?
What fuel pressures ?
what idle fuel trims: LTFT
Have you switched them around ?
What cylinder do you suspect is acting up?
Is your VVT working right?
Any other "unrelated" chassis faults ?
Have you rebooted chassis??
What's the current mileage?
Thread Starter
Newbie
Joined: Feb 2024
Posts: 3
Likes: 2
W212 2010
As I mentioned, I went to 2-3 mechanics because I always like to hear multiple opinions before coming to a conclusion. All of them suggested that the issue is probably with one of the injectors. Tomorrow, I’ll likely go to a local chip tuning garage to check via diagnostics how much fuel each injector is injecting and to see if that’s really the cause. Do you think it could be something else based on what I described above? The part I can answer from what you asked is that the engine is an OM651. The knocking sound started on its own; the car is driven daily, and one morning, the knocking sound just began. It doesn't matter whether the engine is hot or cold—the knocking sound is heard when accelerating, but once the car shifts into a higher gear and the RPMs drop, the sound disappears. Just to be clear, the sound isn’t very loud, but it can be heard inside the car cabin.
