Star Code p201a-001 - misfiring of cylinder 1

[niketpatel71]

Mobilo guy came out and this was the code found by the star machine. The mb technician said that the fault was caused by oil dropping onto a sensor when my dad topped it up as he had spilled a bit. He cleaned it and cleared the light does this seem plauside? Also he said to me the m271 engine is unreliable in comparison to the m111 is he correct?

Thanks guys