This may not be the problem, but it's worth a try and won't cost anything. I had the CEL come on on my '90 300E because a sensor connection came loose. The sensor was the one on the underside of the air snorkle going into the air cleaner. Just a thought.

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Steve

1992 300CE Sportline Sophie
1990 300E Emma - in the family
1979 240D Josephine - sold, but not forgotten
2004 Pacifica AWD

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