Question 1

What is OM651 Diesel Chain Tensioner Oil Leak on the Mercedes-Benz Mercedes-Benz C-Class (W205)?

Accepted Answer

The timing chain tensioner gasket can leak oil. If left unaddressed, the loss of tensioner pressure can cause timing chain rattle and eventual stretch.

Question 2

What is NOx sensor and AdBlue system faults on the Mercedes-Benz Mercedes-Benz C-Class (W205)?

Accepted Answer

Common on OM651 and OM654 diesels. Water ingress or soot can kill the sensors. Often requires replacing both upstream and downstream sensors simultaneously.

Question 3

What is Airmatic air suspension leaks on the Mercedes-Benz Mercedes-Benz C-Class (W205)?

Accepted Answer

Cars equipped with Airmatic can develop leaking air springs or a failing compressor, causing the car to sag overnight. Ignoring it burns out the compressor, pushing bills toward £2,000+.

Question 4

What should I check when buying a used Mercedes-Benz Mercedes-Benz C-Class (W205)?

Accepted Answer

Scan for NOx and AdBlue faults on diesels; Mercedes often requires both sensors to be replaced as a pair.

Question 5

What should I check when buying a used Mercedes-Benz Mercedes-Benz C-Class (W205)?

Accepted Answer

Check Airmatic cars for sinking after an overnight stand.

Question 6

What should I check when buying a used Mercedes-Benz Mercedes-Benz C-Class (W205)?

Accepted Answer

Look for screen delamination on earlier models.

Question 7

What years was the Mercedes-Benz Mercedes-Benz C-Class (W205) made?

Accepted Answer

The Mercedes-Benz Mercedes-Benz C-Class (W205) was produced from 2014 to 2021.

Mercedes-Benz Mercedes-Benz C-Class (W205)

Mercedes-Benz C-Class (W205) Reliability & Common Faults

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