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johannespeters10

Mercedes C Klasse Combustion Misfires

My 2023 Mercedes C Klasse gasoline engine is giving me fits It's got 162101 km on the clock and I'm getting combustion misfires The check engine light is on the engine is running rough it's jerking when I accelerate and I've got reduced engine power I think it's the fuel injector but I'm open to suggestions Could it be something else like a spark plug or fuel pump This combustion misfire is driving me nuts

4 comment(s)

benjamin_kaiser83

Combustion misfires can be frustrating to diagnose Given your symptoms a defective fuel injector is a plausible cause However consider other potential factors before condemning the injector Have you inspected the spark plugs recently A worn spark plug can trigger misfires A failing fuel pump could cause fuel starvation It would be wise to perform a diagnostic assessment including checking the spark plugs and assessing fuel pressure before replacing the fuel injector

johannespeters10 (Author)

Thanks for the quick reply Spark plugs are a good shout I changed them about 30000 km ago Is there a way to easily test the fuel injector or fuel pump without specialized tools I'm trying to avoid taking it to a workshop if I can Also what does fouled mean in the context of spark plugs

benjamin_kaiser83

You're welcome Since the spark plugs were changed 30000 km ago they are less likely to be the primary culprit but a visual inspection is still worthwhile Fouled means the spark plug's firing tip is coated with deposits preventing proper ignition As for testing the fuel injector and fuel pump without specialized tools it's challenging to achieve definitive results For the fuel injector you could try listening to it with a screwdriver as a makeshift stethoscope while the engine is running a healthy injector will make a distinct clicking sound However this method is not precise Given the complexity I would recommend seeking professional diagnostic assistance A workshop will possess the necessary tools to accurately pinpoint the source of the misfire A defective fuel injector can cause unburnt fuel to enter the exhaust system which can damage the catalytic converter

johannespeters10 (Author)

Appreciate the advice I bit the bullet and took it to a workshop Turns out you were spot on it WAS a faulty fuel injector They replaced it and the car is running like a dream again The total repair cost was 515€ Thanks again for steering me in the right direction

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