So been trying to figure out a slew of problems with an 07 Mini Cooper with the N12 motor, 105k miles. The current problem is the motor does not run well. It's very sluggish to respond, has no power and doesn't idle smoothly. It threw a P0015 for B camshaft over-retarded.

After doing researched, the majority of the folks had to retime the cam's. It's been said it could also potentially be the VCT solenoids. So I decided to pull the valve cover to get a closer look.

First take away is a bunch of black sludge. This car was used by my dad and ran low on oil quite a few times. I surmise that this sludge might be evidence of that. He adds oil enough that he doesn't really 'change' it all that often. See first picture.



Second take away. If you take a look at the cams, the part where you can attach the timing tool the flat pieces should line up. In this case, the intake cam if further back then exhaust cam. However I can't tell if that different is because the cam is off a tooth, or if it's within the VCT range of adjustability. See red circles.



I looked at the chain. It doesn't appear to have the top plastic guide, but a metal one with plastic ends. That seems like it might be okay. If I look down on the side where the tensioner is, it appears the end appears to be in contact with the plastic guide. I don't feel movement in the chain, so it's hard to tell if I'm suffering from a stretch chain. I currently don't have the tool to measure slack either.



So I'm hoping to have a second option on this. Should I get the tool to retime the cam and while I do it, should I go down the road of replacing the timing chain, tensioner, etc? My first thoughts is yes just because I have heard chain noise, and I believe I was getting what sounded like chain noise with the engine running in it's current state.

-OR- am I barking up the wrong tree? Perhaps I investigate the VCT solenoids instead?

Also what is everyone thoughts on cleaning up the sludge and how to go about it?

Sorry for the long winded post. I'd like to get his car up and running again.

Thanks!

S

 

Did you fix your problem yet? I recently had a P0015 code on my wife's car "Camshaft B over retarded" so after much reading I decided to swap the 2 variable valve solenoids. They are both the same and easy to get to. After the swap I got a code P0012 "Camshaft A over retarded" so I figured the problem moved from B to A camshafts with the bad solenoid. I replaced the bad solenoid and haven't had a problem since. Camshaft A is the intake and B is the exhaust. I noticed that the new solenoid had more screens on it to block dirty oil. This is apparently a chance they made from the early N12 engines (mine is an early 2008). By the looks of the sludge in your photos the solenoids are very likely clogged.

 

Yes I did fix the problem two weeks ago (forgot to update this post) It turned out that timing chain did hop a tooth on the intake cam for me. When timing the engine with the timing tool the exhaust cam hopped timing as well.

I was planning to do the timing chain any way because I was getting chain rattle from time to time. When I was doing that work, the chain tensioner fell apart when removing it from the engine which really explains why I hopped timing in the first place. After everything was back together, the engine has run like a champ and no more P0015 code. The engine however does consume a bit of oil (measuring daily right now, lost about 1/2 quart in 250 miles), but I think I might have a problem with the diaphragm in the valve cover and a bunch of oil vapor is getting into the intake.

I was tempted to replace the solenoids based on the fact the top was sludgy, but have not pursued it especially after spending over $500 on timing parts and tools, I really didn't want to spend another $225ish on new solenoids with the car now running fine.

S

 

Good to hear that you got your engine timed... did you happen to take any more pictures of your head with respect to the valvetronic gear/shaft on the right rear side of the head? I'm curious as to its position as I've had a head rebuild and the intake cam and valvetronic shaft had to be removed.
If you have any insights or thoughts on how you timed your mini, it would be appreciated. I have the timing tool and can set the cams in place with the stamps at the top. Just need to get the timing chain set and the valvetronic gear in the correct position. Thanks!

 

The valvetronic gear requires the stops to be relearned after the motor is removed, 100% has to be done for the car to operate properly.

The exhaust cam was definitely out of time, if you replaced everything in the timing cassette you should have the codes cleared to see if anything recurs, but just by eye you were out of time.

If you aren't having troubles with the VANOS solenoids, or CELs for them I wouldn't recommend spending the money on them. The oil consumption could be from other things; idling the car on cold mornings uses oil, worn valve guide seals, worn rings, the PCV system on the coopers isn't as much a problem as it is on the N14 engines.

You can do a leakdown test to determine where the leak is, but feel it out over a period of a few months or a full oil change and see how much oil it is truly using between changes. I've seen Coopers that use under a quart of oil and I've seen others that use 3 quarts between changes.

 

I am getting the P0012 code after my rebuild. Exactly how is this done? I did the timing but may have missed this part.

 

What year is your car? The N14 doesn't have a valvetronic motor to relearn the stops in.

You could have either mistimed the engine, have a faulty VANOS solenoid, or oil pressure problem to the VANOS solenoid(s).

 

I have the N14... I replaced the Vanos Solenoid and fixed the issue. Thank you