Hi Scotty. I love the show, I never miss.
I have a 2007 Mercedes C280 4matic with 134,000 miles (W203 M272). The car has always had a vibration at idle. Sitting at a stoplight with the brake on, there is more vibration. Putting it in park drastically reduces vibration. Dealership said they didn't notice anything out of the ordinary. I changed the motor mounts and trans mount. Along the way of ownership, I flushed the transmission, changed both front CV axles and lower control arms, installed new PS pump with aftermarket rack. Now the weird thing is at a stoplight if I turn the wheel a certain direction just slightly, the vibration almost goes away. The vibration got worse after installing the new rack. I don't think there is a vacuum leak but note that at 70mph (only around this speed) the car has trouble keeping cruise (the speedo bounces slightly). I have not done a full scan on obd2 but I already know the car has trans slippage from the flush.
Some say the aftermarket CV axles are to blame because they are not Mercedes. I'm trying to make sense of it.
Thank you.
-Yorker
Some say the aftermarket CV axles are to blame because they are not Mercedes.
Those axles wouldn't have any effect when the car is stopped and engine idling.
Did you use OEM or aftermarket engine mounts? When I installed aftermarket engine mounts in my own car they transmitted more vibration at idle than the collapsed OEM mounts.
Scotty has mentioned periodically that a worn torque converter can also cause a vibration at idle.
Check the large vacuum hose from the intake manifold to the brake booster for cracks and leaks.
Not OEM but Lemforder is a good quality German brand.