I have a 1999 E320 4 Matic with 171,000 miles. The car has been great. Today when my wife started the car the CEL came on and the car was very sluggish while accelerating. About 18months ago while the car was being serviced at an Indie, he replaced one of the O2 sensors, I'mwondering if this could be an O2 sensor issue, or something else.

If the CEL is on, take it in to have the code read. Better yet, you can go to Autozone and buy a code reader/reset tool for about 40 bucks.

I use mine all the time on the Suburban.

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Monika '74 450 SL
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'97 Jeep ZJ Laredo
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