and now a new symptom. The car smells like rubber or electrical burning coming from the vents upon startup. Disappears after ten seconds or so. So I guess I will pull the intake manifold and look for rubber pieces in there. Not sure where else rubber pieces might be stuck that are causing a burning smell to be pumped into the cabin on startup. Still have the MAP sensor pressure improbable code and rough idle as well.
At this point, I'm not much help... sorry about that. But this does sound interesting.. I'm not sure why the vents would have any smell of the rubber inside the intake etc.. that seems odd.
@Sully To catch you up from before I had a P129E code(Manifold Absolute Pressure Minimum Pressure Implausible), rough idle and low mileage. After tearing everything apart and replacing tons of stuff like oxygen sensors and timing chain I found a piece of rubber in the diverter valve housing. Scroll back a few pages for pictures. Everything was fine after I removed it. Code gone and idle was pretty smooth. Fast foward two weeks and it all came back. the code, idle, and mileage. Since it is exactly the same I assumed another piece of the same rubber part showed up in the DV again, but no such luck. Now that I have the burning rubber smell upon startup I think you can see why I am assuming a piece of rubber is stuck somewhere where it is burning but only flowing into the cabin at startup. Maybe some valves open or close a few seconds after turnover or the burning is so mild that once air is flowing it is not noticable. I wish I could find an airflow diagram but all I can find in my Bentley is from the firewall back, nothing from the engine block. Finding a piece of rubber in the DV surpirsed me and I still have no understanding of how that threw a P129E code. So tomorrow will consist of more of a teardown. Intake manifold, DV again in case something changed, and intercooler pipes. Should be a full day so I sure hope to get a result.
Too bloody cold today to do much on the car. Replaced the hot side intercooler. Nothing inside the old one except a coating of oil. Also replaced the diverter valve with the newest model but with my luck lost one of the screws somewhere deep in the engine compartment so now have to wait to get a new one from Minimania. Wanted to use my borescope to look in the cylinders and take off the intake manifold but got too cold. With the engine idling it sounded like I was getting an air leak on the right side of the engine but I have had two smoke tests done the past month so no idea what is going on. Maybe an exhaust leak? Would that not show up on a smoke test and cause a burning smell on startup? Again, only code is P129E.
At Admin's request, here's my $0.02 worth --- Chances are, your yellow DV is an aftermarket replacement and the piece of rubber you found is from the original. The remaining rubber may have remained attached or disappeared into the system, but surely not beyond the FMIC. Double check your MAP sensor part numbers --- MCS sensors are different than JCW sensors, electrically, not physically. Wrong ones will physically fit. Check for correct part numbers here --- http://www.realoem.com/bmw/enUS/select With a new valve cover, chances are your PCV system is OK. However, you need to ensure the rear hose to manifold is in good condition and connected properly at both ends. Crankcase should be at a slight vacuum at all times, EXCEPT during boost when it gets slightly positive. I can't provide numbers, sorry. Low coolant temp is usually a t'stat problem. Consider that during replacement you reversed the two hoses from the radiator. I don't know if that would cause your problem, but hose routing can be compared to the pics in RealOEM. Low temp can also be manually set by a tuner --- has the car been tuned by a previous owner? Typical temps are 210 - 225 deg F --- mine has been set to 180. Oil in the FMIC input is usually from a bad PCV which you've already replaced, and the oil is just "left-over residue". It can also come from the turbo --- excess crankcase pressure will cause the oil return from turbo to crankcase to "back up" and flow thru the turbo seal into the air inlet chamber, ending up in the FMIC. If you have oil residue in the turbo air inlet, and not in the driver side PCV hose, that's probably the source of your oily FMIC. Check the turbo shaft for side-to-side and end play too --- should be zero, only rotation is allowed. Any side-to-side play indicates bad bearings and shot oil seal. Bentley is a good repair manual, and handy to take with you under the car. A better source is --- https://www.newtis.info/tisv2/a/en/ --- step by step instructions with pics and torque specs. For this and RealOEM, you need the last seven characters of your VIN, or you can make the "bingo / link" selections. Can't offer much more --- haven't had to deal with most of your issues, but I'll follow your thread 'til you get it resolved.
For the love of pete. The MAP sensor I have installed is for N14B16C and I need for the N14B16A. So this is probably the error. Thank you @oldbrokenwind for this. Will see in a few days when I get the new one if this is the cause of my issues. So several tear downs and thousands of dollars later we will see if a $50 part is the cause of my issues. At least I will have a half new engine that can support a JCW turbo from DT, so not all is lost.
Happy to help, but don't get your hopes up --- sounds to me like you have multiple problems. Oil in the wrong places shouldn't be caused by the wrong MAP sensor, hopefully, that's an old problem that's already been fixed. Then there's the burning smell and possibly more rubber stuff in the system. Another thought --- someday, if you decide to build for performance, maybe keep this extra MAP sensor and work with your tuner to use it. Might be good for a few added HP --- WITH a good tune. Best of luck and keep us posted.