F10 M5 surging while cruising and cold

[pysical]

Recently bought a 2013 M5. It is bone stock except for resonator and muffler delete. I have noticed that in the morning when it is cold, the car has like a surging feeling while cruising. It only does it while the car is cold. Once it warms up it goes away.

Also, whats the easiest way to monitor and read codes? I have a 335 and using MHD with my Android is super nice. I don't plan on doing anything to the M5 because I am worried about things going bad.

Also, I have NVP Powertrain warranty on the car. If it were to get some tune, would it be able to get reverted without the warranty company knowing?

[BeachM5nster]

Should've never bought a 13 model year

[vafan13]

Originally Posted by BeachM5nster

Should've never bought a 13 model year

Because surging is a well known 2013 issue...

OP: I think surging can be a number of things like dirty MAF, PCV issues, vacuum leaks, etc.*. Cleaning the MAFs would be a good place to start a process of elimination as it is both cheap and easy. Just make sure to use actual MAF sensor cleaner and let them dry a good, long while before putting them back in. If that doesn't fix it, I'd have someone take a look, but you could also try replacing the two PCV vent hoses, which will run you about $100 plus an easy install.




*two of which are related to IAC valve failure and sticking throttle bodies, but I'm not sure this car has an IAC valve and my understanding is the throttle bodies are there as failsafes only and are otherwise always open. I could be wrong on that.