Check Engine Light and Engine Misfire on Mercedes-Benz CLK55 AMG

Failed spark plug wires and/or ignition coils can cause intermittent misfires (rough running); the Check Engine Light may also illuminate. Diagnoses of the ignition system will be necessary to determine which components are at fault.

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Average mileage: 80,000 (80,000–80,000)
4 model years affected: 2003, 2004, 2005, 2006
7 people reported this problem
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problem details
At idle the car misfires and shakes the car slightly around 800-1000 RPM. Over 1500 it's not noticeable. I changed the ignition wires and noticed an improvement in HP but the misfires are still there. Will get mechanic to diagnose which coils are faulty and replace for around $75 each. Not sure what the labour will be. Fuel consumption has gone up lately as well. Might be a combination of this coil issue and possibly the Mass Air Flow Sensor. Will update after diagnostics.