Are we talking about the cats before the O2 sensor or after the O2 sensor? If it's those pre-cat cats before the O2 sensor then you will have issues with the O2 sensor giving bunk info to the ECU. If it's after the O2 sensor then you will be fine.
Regards, Eric

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89 300E "Benzer1" 15.924 Uncorrected
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95 E420 "Benzer4"
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