This is bad!
You'll need to replace the cracked "cam cover-to-air cleaner rubber-thingy".
It represents a vacuum leak on the vac. hose to your Idle Control Valve -which will result in a real crappy fuel economy -which will again toast your O2 sensor -which will cause even worse fuel economy -which again will most likely toast your catalythic converter..

You see? Baaad crack!
How is the rest of your rubber connections for the vacuum system?

And as the others said: Start by testing your O2 sensor.

Freestyler

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Never criticize someone until you've walked a mile in his shoes. That way, when you do, you're a mile away -and you have his shoes!


'86 300E optically converted to '95 E300 (Sold)
-Blauschwarz on silver
-Black leather
-17" AMG & 15" AMG for winter