Cold Start Rattle - 2023 S206 C200 M254 (24,500 km)
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S206 (C200)
Cold Start Rattle - 2023 S206 C200 M254 (24,500 km)
Hi everyone,
I'm new to the forum and hoping to get some insight from fellow Mercedes owners.
I currently own a 2023 S206 C200 with the M254 1.5L engine and only 24,500 km (about 15,000 miles) on the clock. I've always been a Mercedes enthusiast and this is my first Mercedes, so I want to make sure I take good care of it.
Recently, I've noticed a metallic rattling noise on cold starts. It lasts for about 1-2 seconds right after ignition, then goes away completely once the engine warms up or even after just a few seconds. No check engine light, no performance issues otherwise.
I know the older M271 and M274 engines had timing chain tensioner issues, but I haven't found much info on the newer M254 engine with the 48V ISG (integrated starter generator) .
Has anyone with a W206 / S206 C200, C300 or similar M254-equipped model experienced this? Is this likely the timing chain tensioner, or could it be related to the ISG system?
I want to be proactive while the car is still under warranty. Any advice would be greatly appreciated.
Thanks in advance!
I'm new to the forum and hoping to get some insight from fellow Mercedes owners.
I currently own a 2023 S206 C200 with the M254 1.5L engine and only 24,500 km (about 15,000 miles) on the clock. I've always been a Mercedes enthusiast and this is my first Mercedes, so I want to make sure I take good care of it.
Recently, I've noticed a metallic rattling noise on cold starts. It lasts for about 1-2 seconds right after ignition, then goes away completely once the engine warms up or even after just a few seconds. No check engine light, no performance issues otherwise.
I know the older M271 and M274 engines had timing chain tensioner issues, but I haven't found much info on the newer M254 engine with the 48V ISG (integrated starter generator) .
Has anyone with a W206 / S206 C200, C300 or similar M254-equipped model experienced this? Is this likely the timing chain tensioner, or could it be related to the ISG system?
I want to be proactive while the car is still under warranty. Any advice would be greatly appreciated.
Thanks in advance!
