[NZE90]

Originally Posted by WheelNut2

I only checked the ESS for oil contamination. I haven't had a look at the cam position sensors at all.

Any suggestions for diagnosing ESS or CPS at all? Is there a specific parameter in ISTA I can use to investigate them? Should I get an oscilloscope, back pin them and check out the wave form? I really don't want to just fire the parts cannon at this problem.

ISTA can do that too.

[WheelNut2]

Update! Finally. This is fixed!

I installed new Vanos adjuster units (along with the updated vanos timing disks to suit the updated adjusters), new eccentric shaft sensor, new valvetronic motor seal, ESS seal, and a new valve cover gasket (wasnt leaking, but needs to be replacing as part of the service).

This thing runs super smooth now! Its noticeably smoother during low speed and low RPM driving.

Now, exactly which part solved the problem? I don't know for sure. I'd suspect it was the Vanos adjusters, but it could have been the ESS or valvetronic gasket. A buddy of mine who is a long time BMW tech had a quick look at the car in the drive way a few weeks ago and thought it sounded like a vacuum leak. There was a bit of oil around the valvetronic motor, so was it leaking vacuum? It didn't release any smoke when I tested it, so I kind of doubt it. The RPM of the car DOES change now when you open the oil filler cap, which didn't happen before. I couldn't see any damage or issues on the Vanos adjusters or ESS, but that doesn't mean that they weren't the issue.

[WheelNut2]

300km in. First code appears! Who would have guessed?

2A82 Inlet Vanos- "Control error position not reached" "error currently not present"

Why? I don't know. How? I don't know. The still runs well.
There is some kind of software that allows a person to log vanos input and outputs which I guess I'll probably have to get and see what is going on. Perhaps there is a certain temperature, rpm or condition that causes this vanos mismatch. I don't think INPA or ISTA can log data while driving, right? I'll try using Bimmerlink to log a drive to work and see if the actual and requested Vanos numbers match. Maybe I'll swap the vanos position senors and see the code moves from the intake to exhaust.

Oh, also the fuel consumption has increased by about 10% since I put the new vanos adjusters in. Curious. (edit: This is because BC switched to winter gas while I was doing the Vanos work. The fuel is less energy dense by about 10%. Coincidence)

Why is this car so good and also so shitty?! Hahah. Such a pain in the ass, but it doesn't drive like a Toyota so there is so much that can be forgiven.

[WheelNut2]

I’ve been doing some data logging with Bimmerlink. Seems like the Vanos set point and actual numbers are quite close. Idle speed is pretty even. Low rpm driving is still nice and even without lurching or hesitations like before.

The car now runs evenly, but it is coarse. The shifter vibrates at idle and the “smoothness” or “rough running” values seem pretty high. Its in all cylinders so I don't know what's going on just yet. Smoothness numbers bounce all over and are up 1100 positive or negative. Some cylinders are mostly negative numbers and some are mostly positive numbers.

Battery is starting to go now too. Starts are a bit slow. I can see the voltage dropping below 10V when the starter is running (not sure if that’s normal). Perhaps this is contributing to the coarse running. I was thinking to also buy one single coil pack and swap it in to see what happens. I'll update as I go.

CEL came back today (2024-11-01) 2A82 Intake vanos. Maybe the cam position sensor is going?

[WheelNut2]

I swapped the cam position sensors last week to see if the inlet vanos error code would follow the sensor or not. 2A82 code came back on inlet vanos, so the sensors seem to be working properly. Nest I will swap the Vanos solenoids to see if the code follows.