Car was running fine but had CEL on, so instead of cleaning I just bought a new one. if you need one & want to take a chance at cleaning it... it looks perfect from the outside and I didn't touch the bolts for the sensor.

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Current cars:
2001 MB E55 AMG
2003 Honda S2000
2000 Honda CRV

Gone but not forgotten:
2004 BMW 325i 5sp sport
1999 BMW 540i sport
1997 MB E420
1995 BMW M3 coupe