2002 E320 Rough Idle
#1
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2002 E320
2002 E320 Rough Idle
My E320 has 122k miles on it. Runs pretty well but it has an annoying idle when I shift it into gear. When I back out of the garage the idle seems so low the whole car is buzzing. When I shift it into Neutral, the idle speed goes up and the buzzing disappears. In gear, the idle speed seems to be barely above 500 rpm, perhaps 550. In neutral the idle speed seems to be about 800 rpm. Is this normal...I hope not!
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#2
Out Of Control!!
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There are over twenty sensors,devices and control modules that control the N P and D(with brake ) idle.
The issue is not a simple one---Start with plugs, wires, coils then get a good DAS Xentry scan!!
The issue is not a simple one---Start with plugs, wires, coils then get a good DAS Xentry scan!!
#3
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1998 E320
it's your motor mounts. I had the same problem about a year ago.
https://mbworld.org/forums/e-class-w...or-mounts.html
https://mbworld.org/forums/e-class-w...or-mounts.html
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2002 E320
Thanks for the input. I just cleaned the MAF sensor and replaced the plugs with Bosch platinum fusions +. No real change that I noticed. Perhaps a little "perkier", but that could be wishful thinking on my part.
#6
it's your motor mounts. I had the same problem about a year ago.
https://mbworld.org/forums/e-class-w...or-mounts.html
https://mbworld.org/forums/e-class-w...or-mounts.html
#7
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#8
Hey Siopaolover, I feel i have got a problem with the engine and the transmission mounts. At cold startup, there is rumbling inside the cabin. The rumbling soon disappears when putting in D and driving off. The rumbling is lower at idle or in neutral when the engine is hot enough.
Another thing. The transmission shifts very smoothly when accelerating, but makes light thuds when rapidly braking and coming to a halt. There is a clicking noise that can only be heard from outside the car while shifting.
I have a very strong feeling I should replace the tranny and engine mounts.
Any inputs will be very helpful.
Another thing. The transmission shifts very smoothly when accelerating, but makes light thuds when rapidly braking and coming to a halt. There is a clicking noise that can only be heard from outside the car while shifting.
I have a very strong feeling I should replace the tranny and engine mounts.
Any inputs will be very helpful.
#9
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1998 E320
Hey Siopaolover, I feel i have got a problem with the engine and the transmission mounts. At cold startup, there is rumbling inside the cabin. The rumbling soon disappears when putting in D and driving off. The rumbling is lower at idle or in neutral when the engine is hot enough.
Another thing. The transmission shifts very smoothly when accelerating, but makes light thuds when rapidly braking and coming to a halt. There is a clicking noise that can only be heard from outside the car while shifting.
I have a very strong feeling I should replace the tranny and engine mounts.
Any inputs will be very helpful.
Another thing. The transmission shifts very smoothly when accelerating, but makes light thuds when rapidly braking and coming to a halt. There is a clicking noise that can only be heard from outside the car while shifting.
I have a very strong feeling I should replace the tranny and engine mounts.
Any inputs will be very helpful.
I'm not too sure about the transmission problems though, sorry.
Welcome to the forum, btw
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#10
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2002 E320
Thought you'd like to know that you were spot on. It was the motor mounts. One was shot and another one was ready to go. Makes all the difference in the world. Thanks.