03-16-2012, 08:47 AM
Join Date: Nov 2009
Location: Fairfax, VA USA
My Ride: 330CiC, M5, X5
| Before you throw knock/ping sensors in the car, you should try to find some ODBII software that allows you to monitoring live date, possibly even graph it.
Probably the cheapest, but not necessarily the best is either an Android based App called Torque or the ODBWiz USB interface. These are not BMW specific
There is a free and paid version. Paid is $5 USD, used with an ELM327 Bluetooth interface that is about $22 USD you can get data.
Or something like ODBWiz, again, not the best, but for the money not a bad tool.
These tools should allow you to to monitor/graph things like MAF readings and Ignition timing.
The other thing you should do it search the forum here to run a real time MAF test. This has you run a full throttle run in 2nd or 3rd gear and monitor the maximum MAF reading. Then you adjust for altitude and air temperature and see if the MAF is reading the correct. If the MAF measurement is way off, usually it means the MAF is not measuring correctly. Incorrectly functioning MAF at high RPM can impact fuel and ignition timing.