ari

This happens not often but, sometimes in D/R without pressing accelerator my rpm shows 800 with a mild humming noise when I press brake and the car moves twice as fast as it does in D/R without pressing accelerator. Normally it is arround 500 without humming noise. MB dealer here is Veho in Finland does not know what to do?

Sometimes, while I am driving normally it also jumps and I can hear the humming noise.

Any ideas?

- Ari
Oulu, Finland

iewoals

could it be from the a/c cycling on? I know when my a/c is on that the car seems to be slightly louder and runs a bit rougher.

ari

The mild vibration comes and goes away automatically. Don't bother about that much. But, the speed in D/R without pressing accelerator gets double that can be dangerous while parking. Just wondering how this can be normal. Still no answer from Mercedes dealer in Finland (Veho Oy). The guy in the service got a hands on demo of what is the problem as I took him for a drive to show the problem. Then they took the car for service. It was ready after 7 hours and I was told all issues are fixed. But, within 24 hours again and practically every day few times same thing happens.

Any one knows of any email technical service of MB Germany where I can ask about this issue. As a whole I really love this car.

GLKKa2H

An issue, regarding a GLK350 CDI, was subject to a discussion on a German GLK forum early 2010. The "Themenstarter" (OP) noted his GLK jumping from 600 - to 800rpm, apparantly not caused by any "drivers action".

His own assessment of the case, engine below operating temperature, concluded with (which he could demonstrate empirically) two factors leading to the raise of rpm:

1. Turning the Automatic Climate Control (ACC) from off to on, with other loads like seat heaters, rear window heater etc. turned off.
2. Regeneration of the Diesel particlefilter

"Testing" at operating temperature, 90°C, he didn't get the symptom.

The OP forwarded request(s) to his dealer, and finally got answers, which in short (from German) goes:

1. Dependent on the engine coolant temperature and selected Auto mode of the ACC (or "Manual mode" and air flow 1 or higher), is the electrical heater of the diesel engine activated.
2. With increased current load(s) will the engine get a signal to increase the rpm.
3. As well can the rpm raise during the regeneration of the particlefilter.

Maybe you should bring these statements to your dealer and note their (any) response?

The OP as well forwarded his questions/concerns to "a higher level" in the MB system, as he, like you, regard the raise of the rpm being a safety issue. The response from MB was the one from the dealer.

Regards

ari

Thanks GLKKa2H, I will inform this to our dealer here. My only concern is the sudden increase in rpm while parking can be a big safety issue. As if the driver is not concentrating hard it might lead to a accident.

Thanks a lot!!!

GLKKa2H

Olkaa hyvä!
PS. I take it the nice market downtown is now closed for the season, if it's still being held there.

ari

Kiitos!!!
Yes, market is still there in Torinranta near police man statue.

mjhawkins2346

Finland? The car is probably trying to stay warm enough.

tazzz3.2

hello,
sorry, haven't read all the post, i have the same thing, it is normal condition when the particle filter is in recycling mode. often or not, depend of your driving quality, i mean, the kind of road you use to drive, small or hight speed road
brgds