Persistent p0012 on N52 X5
 

Hi everyone. This is my first post but it wont be the last! Maybe one day I can help someone else but for now I need your advice about a persistent P0012 code on X5 N52 ("camshaft position sensor a overretarded on intake bank 1").

What it does :

-weird idle on start up, goes up to about 1.5k then just under 500, then up again and settles at 600

-also does this when arriving at a red light

-when i erase it it comes back on the next drive.

-does not affect driveability in the least

How it happened :

-changed my OFHG which caused spillage of coolant in the oil passage and a oil level malfunction light, which turned off after getting up to temp and letting the steam out. In the process I may have yanked a tiny bit on the camshaft position sensor wire, and I definitely sprayed a lot of brake cleaner on the front of the engine where the camshaft position sensor is.

two days later I got a p0012 code. Changed the oil twice after that, the first time with seafoam.

I then cleaned both VANOS solenoids, removed the camshaft position sensor and cleaned it (it had a bit of peanut butter like mix of coolant and oil on it), removed my oil filter to see if the cage was secured inside the cap, and the code stayed

-swapped camshaft position sensor a with camshaft position sensor b, the code stayed and still comes from sensor a

-what next?

Thank you!

Describe HOW you did this, in detail.

I removed them and blasted with compressed air but they already looked almost perfectly clean.

recommeded technique is to use carb cleaner solvent, blast them while actuating them w 5 V (not 12). See if there is a change over time as they get cleaner, you want a nice crisp click.


Without actuating you cannot get into the 'other side' of the internals.

But they were both very clean though. Could introduction of a little bit of coolant really damage them like this?

Dunno.


They get sludged up in normal service (ie even without coolant)


Just because you had a coolant contamination issues doesnt mean thats the only issue. Maybe something pre-existing got flushed into the 'noid??

Anyway, im just passing along how you clean them. Just so as you go forward, you can keep in mind that, PERHAPS, you havent completely ruled that out. Do you have a computer that will let you ruin a VANOS functional test??? THAT would be most useful

Thank you. I do not have such a computer but Ill try cleaning them again the way you said.

How long have you owned?
Idle fluctuation sounds more like a vacuum leak issue.
Check the eccentric shaft sensor connection under the beauty cover for oil.
Swap intake and exhaust solenoids after you clean. If code moves to other bank, replace solenoid.
Inspect solenoid connectors and wiring for damage.
I get this code every 6 months or so. I usually clear. Last time I took X5 out and gave it a good thrashing....several WOT runs with 1-2 and 2-3 shifts over 5K. CEL turned itself off.

Ive owned it for a while and havent had this issue but what makes me think you man be right about the trashing is Ive been running a bad radiator that overcools the engine (thermostat bypass through transmission oil cooler), combined with the cold whether here and a bit of coolant in the oil, some passages may not have gotten the proper oil flow. I changed the radiator last tuesday and the idle fluctuation may be less now. I will check the eccentric sensor, and I have swapped the solenoids already. Thsnks!

Low temp will set code(s). Unlock the OBC or "hidden menu", add up last 5 digits of VIN, enter this as code, go to test 7 and monitor coolant temps while you drive. Mine runs 98-103C. Radiator is not likely cause of low coolant temps, thermostat is, but don't change until you check the OBC.