I would think you have to adjust the mixture after 'un-clogging' the cat. -Preferrable while measuring CO from the exhaust.
Mine went from 7 mpg to 23,5 after replacing fuel distributor and cat. -And a good mixture adjustment.
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
-17" AMG & 15" AMG for winter