e61/n54 I'm a magnet of 'what can go wrong'
 

So we have ~90k miles on the 535 wagon now after a year of ownership. We bought it in June of last year w/ ~58k and had ~73k in April... One thing ownership of it has reinforced for me is BMWs are very predictable.

- Soon after we bought it we had the HPFP go... replaced by BMW under warranty.

- In June, I found a small amount of water in the battery area. Traced it back to clogged sun roof drains. Did the clean out and was amazed how carefully the clean out had to be performed. I used compressed air first, but didn't get the blockage to clear until I went with a pipe cleaner and went from the sun roof side through the port. Both sides were clogged.

- Over the weekend the electric water failed. It made it to 90k which seems pretty good for these electric pumps. The one in my 135 on made it 33k miles before crapping out.

- While it was in there, I'm having the carbon cleaning of the intake valves done. See attached pics of the "before." I was having minor/occasional mis-fires/roughness that I expect this will cure.

I *think/hope* that is all the major N54/e61 gremlins. I'm hopeful that as long as I keep after the sunroof we should be in good shape for another couple of years. Anything else I should prepare for? The pro/con of all this is BMW issues are so well documented and so predictable that there are very little surprises. The con is these issues are also very hard to avoid (ie: prevent from requiring attention).

I will say it is an awesome car for road trips. Super comfortable, super fast, etc. It's been good at hauling crap around, and my wife likes it as a daily drive. It was also solid in the snow last winter. I wish it was a 2010 had comfort seats and comfort access, but for what we paid for it we've gotten good value for our money. If we can get 3 more years out of it I'll consider it a win...

Interesting. I wasn't aware BMW went back to the oval intake ports.

That is pretty gunky. Makes me wonder how bad it is on my wife's Mazdaspeed3, which has almost 150k on it and is a direct injection engine as well.

Good luck.

Carbon cleaning complete. First impression is it seems much smoother. It pulled strongly and I noticed no mis-fires/hesitation under load. I'll need more time with it to be sure all is well now.

Interesting. I never attempted the clean out myself, but was under the impression that to do the rear drains you had to pull the headliner. How did you get to them?

I pulled the back half of the headliner down (disassembled from the rear hatch forward until I had sufficient access). If you put the sunroof in vent mode you can get to both sides of the opening from inside the headliner. It's not that far back from the rear hatch.

Part of the design flaw is there is VERY little height at the back of the sunroof channels to hold water if the drain is not completely free and clear. Even with a 3/4 open partial blockage excess water just flows down the channel and right over the maybe 1/8" high rear lip onto the headliner. If there was more of a containment area for the water at the back of the channel, it could buffer the flow through the drain hole. In fact I wouldn't be surprised if a heavy rain could overwhelm the drains even when fully open.

Looks good. Did you do it yourself, and if so, how?

My mechanic did it. $500. Basically take off the intake manifold cover up the engine bay as best you can and then sandblast the intake valve ports w/ walnut shell 'beads'. Vacuum out the mess and put it back together.

When I first started it after picking it up it was rough/unstable for about 30 secs. I'm guessing it was burning off the residual left overs. Since then it has been silky smooth. I drove it this AM and tried a number of different scenarios (low speed cruise, high speed, hard accel, light accel, etc.) and it was noticeably better in all situations. No hesitation, no mis-fires, less vibration.
https://www.youtube.com/watch?v=ONp6gQXpyKU

Now it just needs to stay this way for a few thousand miles so i can stop worrying about what's next.

For those of us lucky enough to have Panoramic sunroofs, this is a friendly service reminder to check your drain plugs. :rtfm:

Did I mention we got 3" of rain here this week.

Damn.

I hope not to add f10/n55 to this thread (or create a similar thread). They are getting quite complex.