I have a 2012 R58 S with 150K. Car has lacked in power since around 98K miles. I've replaced turbo with a new Borg Warner unit. Changed the Down pipe with cat, checked the intercooler and piping, no restrictions. Car has zero codes and high pressure fuel pump is around 17-1800 psi while driving. I purchased car at 70k and have done oil changes at 3 to 3500 mile intervals with Amsoil sig 5/30 religiously. I'm suspecting the valvetronic system, but would think that would throw codes. I'm out of ideas and at my wits end. Any ideas would be appreciated .

 

At 150K have you looked at the intake for carbon buildup? I was looking at doing that in another 10K till a Columbus, OH idiot decided my Coupe needed body work.

 

yes, I did the intake valve blasting about 15k miles ago. They really weren’t that bad actually. My daughter has a 2012 R60 from which I traded multiple sensors without any change in performance. I’m still leaning towards the valvetronic actuator. What baffles me is that there’s no trouble codes or CEL.

 

It's very possible that you won't get a trouble code or CEL until the VANOS solenoid actually fails. But just a bit of dirt or gunk on the screens in the VANOS device can create mayhem as the VANOS solenoid on the intake side tries to communicate engine condition to the Valvetronic motor. The single Valvetronic motor on the driver's side of the engine then takes the VANOS solenoid data to either retard or advance how much lift is required to open the intake valves to maintain peak power and efficiency.

If you suspect an issue with a VANOS solenoid (N12, N16 and N18 engines have two of these), pull the device on the intake side of the engine and take a look at the screens on the device - they should be scrupulously clean. It's unfortunate that the intake VANOS can be a PITA to remove, so if you're going to make that much effort then you may as well replace it, as opposed to simply cleaning it. Here's what my intake VANOS looked like at 85000 miles. I had no reason to pull it beyond my own curiosity, but it was simple matter then to just replace it.


Intake side VANOS solenoid, not too grubby but replaced nonetheless

Sergeant Major - again, my condolences on what happened with your Coupe. Second, carbon buildup can be a real issue with all direct injection engines, which are in all MINI Coupes. Here's what my intake valves looked like at 85K miles. I was surprised to see that the intake valves and stems were as clean as they were, and just as surprised to see the amount of carbon buildup in the intake passages upstream of the valves. Note that in the photo my camera actually knocked off a piece of the buildup just by bumping it; I could actually remove a fair amount with my fingertip on the parts that I could reach. I was also surprised to see how much oily buildup was in the intake manifold as well as in the throttle body itself. It cleaned up fairly well after a spraydown of carb cleaner and a little elbow grease.


Note the loose chunk on the backside of valve


I didn't do any cleaning here - just as it looked after pulling the intake manifold

 

I actually replaced the intake vanos solenoid, but it had no effect on the issue. I’ve also blasted the intake valves. I’m trying to find the ISTA software to download so I can try and monitor the valvetronic Not having much luck. Anyone know of a good download that’s reasonabley priced?
Thanks again for the responses

 

Well, first of all, you are military of former military as you understand my name/title. Actually, it is CSM now.

I know the N18 has less issues but with 140,XXX and little to go on, I thought I would ask. A lot of us bought these used so know little to no maintenance history, what fuel was used etc. Trying to troubleshoot a difficult mechanical issue via the internet is hit and miss. There is no substitute for being there, feeling/hearing it.

Thanks for the condolences, been out for military training all week. Still don't even know if the other driver was insured or not. If they are, I found several replacements for mine. If not, I found a couple of "FLOOD" damage totals that would suit my purpose well. Flood vehicles rarely bring very much in particular from Florida (likely salt water)

I was SO BUMMED on the drive out (OH to VA, Ft. Gregg-Adams formerly Ft. Lee). I took another different route that would have been a total joy to drive in my Coupe. My 2013 Chevy Avalanche got me there but, it corners like a brick.

 

In New Orleans right now:

In redd.it, here:

Command Sergeant Major - respect. Former Navy Corpsman here, 11th Marines, back in the '70s. Good times.