HI everyone!

I have a 2006 R53 (Cooper S). I am getting the following codes:

P0171
P1237
P1688

My engine mods are as follows:
Light weight crank pulley (Yes I know the long term damage it causes....)
17% SC pulley
DDM Cold air intake
One ball mod exhaust

I have a brand new belt (nice and tight). I replaced the MAP and TMAP sensors (BMW parts not cheap knock offs). My BPV seems to "flutter" a bit around 3k RPMs but it feels like it has the right resistance on the spring and the small hose on it appears to be in good condition. I drive 40 miles each way to work and most days lately it is going into limp mode once per drive. Pull over, turn it off and on, and it goes back to normal but the MIL/CEL is still on... I am in desparate need of a clutch replacement but my garage is full of a minivan with an engine replacement project ATM so it will be a week or two before I can install the clutch. Any ideas as to what may be causing this? My vacuum hoses "appear" to be OK but maybe I need to do a smoke test to see if I can find anything. I was getting a MAP code originally that caused me to replace those sensors. I did one (MAP I think) while I waited for the TMAP from the dealer (out of stock) then swapped that out and went back to normal for a couple of weeks and now back to this. My fuel economy is also horrible pretty much regardless of how I drive. I used to get about 26-27 driving with some spirit here and there but now am averaging 21-22 driving under 3k RPMs at all times... Please help!

Thank you!!!

 

No ideas what I should be looking at?

 

Have you looked up the codes to see what they are pertaining?

 

this link should get you started https://bmw.oemdtc.com/108/dme-fault...-mini-cooper-s
but you need to take into account all your codes they all relate to fuel air mixture issue ...air leak possibly or possibly bad Map sensor

 

Thanks for the suggestions. I zip tied my bypass valve shut to see if that narrows anything down. Since I did that, I am seeing P1237 and P0108.... I also did a smoke test and didn't find a leak. I am wondering if I just got a bad sensor from the dealer when I replaced the MAP and TMAP. I wonder if they offer any sort of warranty.

 

Well, I am finally getting closer. Turns out I had an O2 sensor going crazy.... That was causing limp mode and the poor performance/weird stutters... Now I am still fighting the p1237 code. I have replaced both the MAP and TMAP. While troubleshooting this, I noticed my BPV is not opening at idle and is effectively always closed. The spring feel right (hence it being closed). Shouldn't this be open at idle? The only hose on it is the small one that goes from one side of the BPV to the other. That hose seems to be seated and on just fine. Where is the vacuum that operates the bypass valve located? I could reinstall my VGS mod too see if that makes a change. I am sure this is what is causing my poor mileage and think it may be part of why I am getting the P1237 code.

Thoughts?

 

So turns out in the end, it was the supercharger intake tube and crush gasket. The part where the screw holds it in was broken. I also did a Detroit Tuned BPV from Way at the same time so it could have been the BPV also but the car runs great now!