Hey guys! My name is Jon and I'm new to the MINI scene but I do have previous experience with working on cars but it seems my MCS has got me stumped to say the least. I just bought an 04 MCS with approx. 165,000mi (I know it's kind of high) and the maintenance of the car seemed to be a little neglectful from the previous owner. I noticed that the car had a little bit of a "yoyo"ing effect while driving at steady speeds at around 3,000rpm or when at WOT at around 5,000rpm. I decided to see if the car had any stored codes and I found that it had P1106 which led to the map sensor so I changed that. It seemed to fix the problem for about a week but it came back and it seemed to be a little more harsh then before so I decided to do a maintenance overhaul on the car. I replaced the following parts on the car:

• ATI super damper
• idler pulley
• serpentine belt
• DT BPV
• intake tube and gasket between supercharger and TB
• replaced supercharger oil
• and misc. bushings and gaskets that were leaking or worn.

After putting the car back together the car kept throwing P0136 which led to the O2 sensor post cat so I changed that and cleared the code. The car ran fine for about 2 days then it finally threw the codes that I have no idea how to fix, P1237 and P1688. I think I would be able to rule out the crank pulley and BPV since those items are brand new. And I'm pretty sure the MAP and TMAP sensors are fine because they are reading within spec from what I can see on my OBD2 reader. Also I'm pretty sure I don't have a vacuum leak because I did a smoke test and found nothing. At this point I'm not sure where to go from here. Any help would be appreciated. I'm trying to get this car back up and running as soon a possible. Thanks in advance for your help and sorry for such a long post, it's been an interesting month with this car.

 

Do you have an aftermarket SC pulley?

Mark the SC pulley and the crank pulley with a paint marker and see if either are spinning on the shafts.

You'll want to mark the bolt to the crank pulley, but to mark the SC pulley you'll have to get creative if it doesn't have a hole in the center to mark in.

 

Thanks for the reply! No upgraded supercharger pulley. The engine is completely stock...for now I'll go ahead and try that to see if there's anything out of the ordinary. Thanks for the advice

 

Alright so I tried marking the crank and sc pulley and drove it around a little bit doing somewhat spirited driving. Doesn't seem like the pulleys are spinning on the shaft. I'm starting to get really frustrated with this car and it's a shame because when it is working properly it's the most fun you can have with your pants on Is there anything else that I can check? I read something online about a software update v38 that's supposed to fix the yoyo effect but I'm not sure if the car ever had that update. Is there a way to check on that?

 

The MINI is officially fixed! Alright so after a couple of sleepless nights making sure I buttoned everything back together correctly I finally decided to look at the Detroit Tuned BPV to see if maybe it was getting hung up on something. It looked fine but I ended up taking it off to inspect it further. To my stupidity I noticed that I never made sure the adjustment of the valve was correct before installing it so the BPV was partially open during WOT which ended up causing those two codes. I'm just glad I can finally enjoy all the new modifications I installed on my MCS. hopefully it's quite some time down the road before I run into another problem.