Please help - CLK 350 transmission "issue"
 

Hopefully someone can help with what seems to be an unusual problem. I have a 2007 CLK 350; P2 with sport package with 18k miles. I've been to the dealer several times with no resolution. Summary of problem: Doesn't happen all the time, but occasionally when I attempt to accelerate while already moving the transmission seems to fail to respond or downshift. When I press the accelerator, RPM does not increase, power does not increase; car simply seems to glide for around 3-5 seconds. Vehicle is definitely not slipping into neutral, as there is NO RPM increase, even when floored. It seems as though the accelerator is not communicating with the engine. Eventually, usually after repeated mashing of the accelerator, it seems to "wakeup" and accelerate. Speed is usually between 20-40mph; generally happens at the worst time, when attempting to merge into DC traffic! Dealer can't recreate, and keeps telling me there is a "normal" delay in gear changes in any automatic, but I know this is definitely not normal and is borderline dangerous. Selector is in "S" mode. I appreciate any insight you may be able to offer as this has progressed to beyond an annoyance. Thanks again!

Hi!

I have exactly the same problem. Two days the car won't accellerate correctly. Driving the german highway is almost impossible, takes 3 miles to reach 80 mph. Today while driving on the highway, the problem was gone. One second it was there, next everything is ok.
My car is a C220 CDI with 248.000 kilometers (155.000 Miles).
Now I don't know what to do...
Any ideas?

AmaG

EDIT:
Have you tried this? http://www.mbworld.org/forums/1425351-post5.html
My battery ran flat last week, I bought a new one an installed it the next day. Maybe this
caused a reset in the trans-system. Somewhere I read "there seems to be no substitute for slammin' the throttle and letting the system learn by itself." (http://forums.mbworld.org/forums/w21...t-happens.html)
And indeed, the problem solved while driving the highway 15 minutes with gas pedal fully pushed down.
I'll try the reset tomorrow!
/EDIT

Problem: Solved!
 

Problem: Solved!

Resetting the ECU did not work at all. So I went to Mercedes. They did a quick check which said: The air mass sensor was defekt. This caused the engine to go into failsave mode.
Check this: Chose "2" on the automatic transmission an drive faster and faster. Watch the rpm. If you cannot go over 3000rpm the your engine is in failsave mode.
Changing the air mass sensor costs 50$ plus 100$ for the sensor.

AmaG