You cannot hold a high rev in static mode. with no load. It will cut. It is supposed to do that.
It prevents an over rev by someone bleeping throttle.
This has been researched on other forums.
230's also seem to have a very slight stumble at idle, esp in neutral.

http://www.benzworld.org/forums/foru...iew.asp?fid=26

Bazzle

 

how much is the mileage?

 

I never use A/C...
But as you said, is it really a missfire or just small variations during idle ?
I never had any missfire at other RPM than idle.
Maybe I will try to have an engine diagnostic to my mercedes dealer.

 

The SLK230 is prone to the spark plug conectors causing tracking marks down the porecelin on the spark plug. If you remove your spark plugs, always keep them in order on the bench and then examine them for small black lines along the length of the porcelin. If these lines are present, there is your miss, but you must also replace the connector to the spark plug. It is most common on the connector under the coil pack, and is available seperate to the coil pack.

As for the SLK320, I would assume that they have checked the air mass sensor, purge valve, compression and checked for faults in the memory which would relate to the miss. Electrical missfires are normaly picked up as a fault code. From there, it should be checked for water. Check the fuel filter first of course, but the fuel rail doesn't have a return like the earlier models, and if water does happen to get into the rail, it just floats around causing problems.

Hope this helps one of you guys at least.

 

I have a 99 slk and took the red cap off where the spark plugs should be put how do i take them out
i have had several cars and changed dozens of spark plugs but this looks like nasa stuff please help..

 

tell the dealer to inspect the wiring harness
the harness get contaminated with oil from the cam adjuster on the front of the engine
oil could be at the engine control module cause running probs
if your ceck engine light is on with a code saying o2 sensor short to ground/positive thats probably your prob
there is an updated adjuster and engine wiring harness that must be replaced and maybe engine control unit
all the dealer has to do is unplug the module and see if there is oil at the module
if not unplug the o2 sensor before the cat converter and see if there is oil
there is a bulletin on netstar about this condition

 

I was told that is normal when not under load. Mine does the same thing.