Local Mercedes dealership advised that Cam shaft adjusters were bad and had read engine codes to prove it. Took it to two local independent repair facilities and they could not confirm the codes. Price by dealership $5300.00 - the local Mercedes independent shop fixed it the first time for $3200.00. Second time less than a thousand miles later??? The car is in for analysis now.

Same problem again. Knocking or rattling noise - sometimes. Sounds like octane knock but consistent when occurring. Mostly at very low speeds.

From what I've read, this 4 cylinder turbo engine has a chronic problem with the cam shaft adjusters on the C250 Mercedes and the 2012 is the worst. Unfortunately you don't know this until you experience the problem, search the internet for others that have had the same problem and come to find that Mercedes has not done a recall on this major engine malfunction.

Shame on Mercedes Benz.