Mercedes-Benz CLA: M270/M282 Timing Chain Cold-Start Rattle (C117/C118)

CLA models from C117 (2013–2019, M270 engine) through C118 (2019–present, M282 engine) carry the same oil-pressure-dependent hydraulic chain tensioner found across the Mercedes compact platform. Cold-start timing chain rattle is widely documented across CLA 180, CLA 200 and CLA 250 variants. The performance-oriented CLA 250 with its higher-stress M270 specification is particularly noted for tensioner wear when oil change intervals are extended.

• Rattling from front of engine on cold start for 2–5 seconds
• Persistent rattle in neglected examples
• P0016/P0017 OBD fault codes
• Rough cold idle that stabilises once oil pressure builds

1. 1

   Cold-start test is essential.

2. 2

   Listen at the front of the engine for chain rattle in the first 5 seconds.

3. 3

   Inspect oil service records and verify intervals.

4. 4

   The CLA is commonly bought as a prestige daily driver — urban use with extended oil intervals compounds the risk.

5. 5

   Scan for timing-related fault codes before purchase.

Parts involved: Timing chain.

$2,000 to $4,500 at New Zealand independent workshop rates. That is for this job on its own, not for the car.

An estimate, in NZD, for the repair as normally carried out. What a specific car costs depends on which part has failed and what it damaged on the way — treat this as the floor for a negotiation, not a quote.

• “Has the timing chain or tensioner been replaced?”
• “What oil and interval schedule has been used?”
• “Has any cold-start noise ever been noticed?”

The failure described above is documented in published sources — owner forums, technical service bulletins, recall notices and workshop write-ups — held in our fault database. The inspection instructions and the cost estimate are KickTyres’ own interpretation of them, and it is a starting point for an inspection rather than a manufacturer statement.