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2012 C250 Engine noise.
#1
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Thread Starter
2012 C250 Engine noise.
I was wondering if anyone on here is experiencing an engine noise from the 1.8 turbo motor. Seems to be mainly when cold/start up. Sounds like very loud fuel injectors. From upper engine area. After warm up, quiets down a lot. Was hoping for some type of suggestions prior to having it services at BM Dealer. Also, no MIL light or performance changes. In car - unnoticable, only from outside.
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bear330 (10-19-2022)
#2
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2024 GLS450
Mines pretty quiet all of the time - even on a cold startup.
I know the M271 Kompressor engines have some timing chain issues they are prone to, but not sure about the M271 Evo that we have.
Hopefully Glyn can chime in - I seem to remember he was the one that knew about the chain issues on the older 271s.
I know the M271 Kompressor engines have some timing chain issues they are prone to, but not sure about the M271 Evo that we have.
Hopefully Glyn can chime in - I seem to remember he was the one that knew about the chain issues on the older 271s.
#3
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The DI engines have distinctive sound. Slightly diesel like & normal.
Make sure you have the latest ECU flash next time you service.
Otherwise can be a lazy hydraulic lifter.
The chain noise is front of engine. Rattle at cold start that shuts up as oil pressure comes up. If you ever hear this rattle pull a new chain with use once tensioner element immediately.
Make sure you have the latest ECU flash next time you service.
Otherwise can be a lazy hydraulic lifter.
The chain noise is front of engine. Rattle at cold start that shuts up as oil pressure comes up. If you ever hear this rattle pull a new chain with use once tensioner element immediately.
#5
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Appreciate the response. Will be taking it in next week. We'll see what dealer says.
Also, definitely sounds like the top of engine. Not the front. Hope that eliminates any timing concerns.
Also, definitely sounds like the top of engine. Not the front. Hope that eliminates any timing concerns.
Last edited by arketect; 03-12-2014 at 06:59 AM.
#6
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A burred camshaft adjuster can sound very like the chain. It rattles at cold start & shuts up as oil pressure rises. Not very common on newer M271's & derivatives.
There is a deburring procedure that never works. Replacement is all that works.
It's likely just DI noise. They multipulse the injector to make it as quiet as possible.
There is a deburring procedure that never works. Replacement is all that works.
It's likely just DI noise. They multipulse the injector to make it as quiet as possible.
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#8
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MDMG ~ Have they ever reflashed your ECU? There was a bit of playing with tuning on early DI cars. Changing injection can reduce & flatten that sharp pressure rise that sounds a bit like minor knock. I'm also convinced that there is a little bit of exhaust system effect after the exhaust has seen some use.
Last edited by Glyn M Ruck; 03-12-2014 at 01:40 PM.
#9
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MDMG ~ Have they ever reflashed your ECU? There was a bit of playing with tuning on early DI cars. Changing injection can reduce & flatten that sharp pressure rise that sounds a bit like minor knock. I'm also convinced that there is a little bit of exhaust system effect after the exhaust has seen some use.
I have noticed more carbon on the exhaust tip between detailings, though. I can deal with that - particularly since after going over everything with a boroscope I did not have any carbon buildup on the intake side of the house or valves.
Last edited by Glyn M Ruck; 03-12-2014 at 01:40 PM.