The camshaft adjuster solenoid (which is related to the variable valve timing system) may fail or timing chain/balance shaft components may wear, resulting in illumination of the Check Engine Light and various drivability issues. Mercedes-Benz has released a service bulletin outlining specific repair instructions depending on fault codes stored.
Check Engine Light Due to Faulty Camshaft Adjuster Solenoid on Mercedes-Benz E550
Average mileage: 46,500 (20,000–70,000)
9 people reported this problem
2007 Mercedes-Benz E550 46,000 mi, Visitor
check engine light came on. Dealership said it was a $5000 to $6000 repair. Timing and camshaft parts were worn out. This is a problem that mb knows about. Bad design. These parts should not wear out in 45,000k miles on any car. Shame on mb for not recalling.
2010 Mercedes-Benz E550 20,000 mi, Visitor
I complained to dealership 6 times about problem and light still comes on.... Less frequently now but problem still exists.