Hello I recently bought a 210k mile e60 530i but the acceleration off the line is very weak. The message reads "engine malfunction increased engine loads may damage catalytic converter". I decided to get AutoZone to scan for codes and I got P17e1, P0420 and P0430, which say "catalyst system efficiency below threshold in bank 1 and 2, P0700 which says transmission control system malfunction indicator lamp request, a misfire in cylinder 5, and a misfire detected with low fuel. I understand what I got myself into when I got the car as I mean for it to be a project car, but I am curious if anybody here has dealt with these issues. I'm assuming the transmission and catalytic converters both need to be fixed, which I'm also assuming will cost me a fortune. Any help is very much appreciated thank you.

 

I don't think you do fully understand what you got yourself into. BMWs are not like normal cars. There's a lot of troubleshooting with the correct tools. The OBD2 reader you have is not going to do much with assisting you with the right fixes. You have 2 big things going against you when you purchase a project car, the knowledge, and the correct diagnostic tools. You need to start with basic maintenance and then go from there.

 

Yes, what seanjordan20 said!

FWIW, sometimes when you have a persistent misfire, it can send so much raw fuel into your cats that they get clogged up, creating some really odd back-pressure (and most likely, additional misfires).

But yes, first go figure out how to get INPA and/or ISTA running on a laptop, or buy a BMW-specific scan tool (I got an Autophix 7910 for not much over $100 IIRC, and it does nearly everything that the more fiddly laptop-based systems do, though it is REALLY nice to have both).