I have several codes on my 01 ml320 . Several of the codes show on my scanner twice such as p0300 p0304 p0305 & p0306 and I also see 2 other codes p0410 & p0150P? I dont know where to start, my car doesnt accelerate properly I have to floor it in order to go faster than 40 mph and when I do that the car starts to shake or engine really bad. Now before the codes p0410 & p0150p showed there was a code p0432, the code for main catalyst threshold bank 2 whatever that code is that was there and I purchased a cat for $650 and didnt get it installed and continued to drive. Well that code doesnt show up anymore im very confused. I got a tune up and scanned and it solved a few misfires temporarily but the p0432code was still there but I dont know if I should return the cat and just replace the MAF sensor and the o2 sensor or replace the cat and the sensors . Im trying so save as much $ as possible . Im hoping the cat isnt the problem and I can return it . SOMEONE PLEASE HELP ME !