U.S.-spec e90 2006 BMW 325i (pre-April '06). 3.0L N52B30AE engine (n/a, port injection). 155K miles, automatic, no mods. All faults/data read with iCarsoft reader.
After a year of driving it, 5 months or so ago, I started experiencing some intermittent misfires. I replaced a different coil on two occasions (w/OEM Bosch) and each time that seemed to fix the misfire.
Then about 2 weeks ago another misfire started in cyl 6 and seemed to become permanent. Fault codes pulled at the time:
2A34 - Valvetronic, eccentric shaft sensor: reference
2A32 - Valvetronic, eccentric shaft sensor: reference
2A47 - Valvetronic, eccentric shaft sensor: plausibility
2A37 - Valvetronic, eccentric shaft sensor: plausibility
2A1A - Tank-venting system, function
2E35 - Fuel injector, cyl 6, activation
Saw lots of oil in the eccentric shaft sensor clip (a good indicator of sensor failure), so cleaned and replaced the sensor, gasket, valve-cover gasket and Valvetronic motor gasket with new OEM components.
To be safe, I replaced the remaining old coils with new Bosch coils, and changed all six plugs to new recommended iridium plugs.
Cleared all faults, switched the car "on" twice as recommended, Valvetronic motor made some noticeable clicking. Started the engine, no Valvetronic faults or noise, but the misfire remained and the "2E35 fuel injector cyl 6" fault returned and would not clear.
Swapped out cyl 6's fuel injector w/new OEM, cleared code, started the car and it seemed to run fine for a week or so over the course of 200 or so miles.
=== WIN!! (or so I thought) ===
Today at cold startup, car idled high, then engine stumbled and shook (but didn't misfire). I heard some clunking under the hood, and what I think were some intake manifold backfires. After a few minutes the idle settled but throttle response was noticeably lagging. New fault codes:
2A38 - Valvetronic, monitoring, sluggish movement
2D06 - Air-mass system
2A43 - Vaveltronic, thermal overload protection: warning threshold
Cleared codes, disconnected and reconnected battery, and started car again. Same symptoms. New Faults:
2A43 - Vaveltronic, thermal overload protection: warning threshold
2A39 - Valvetronic, adjustment range
Did some Datastream viewing and saw the data in the crappy collage below. I have no idea what I'm looking at, but it seems to me that something is seriously out of wack with cylinder 5, and maybe all the cylinders.
I'm thinking and hoping that a DME reprogramming might be all that's needed, but I'm wondering if it could also be that the Valvetronic motor is going out now. Weird to me that all this is happening at once.
Also might be important: I have been experiencing sluggish starting since I bought the car. Always thought it was an old battery or starter, but I've been seeing this symptom tied to Valvetronic faults more and more.
Thoughts/guidance?
