My W202 C220 1994 model may have same symptom. Can I confirm that my 4 cylinder are connected to 2 coils with 2 spark plugs wire connected to each. I notice although on the same series that number 2 & 3 are interswitched. Could this cause a misfire or similar symtom. Confirming also some of the wiring harness insulation is definitely cracking.
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