Z4 Coupe 3.0si Valvetronic issue

[ryanmcde]

Hi Everyone,

Was driving my car the other day and noticed a drop in power, but was still driveable.

I did an OBD scan ,using a Carista scanner, and got the following error:


2A39 - P1024 - VVT-Self-Learning Function Faulty Lower Learning Range (Bank 1)

and a FF00 error which I haven't been able to find any link to.

After some digging on forums, I found some suggestions of the eccentric shaft sensor potentially being the issue. The connector was clean and when running it disconnected I got new errors coming up - so I'm confident its not the sensor.

Then driving it to work this morning the car went into a limp mode, basically wouldn't rev above 3k. I scanned it again and still only the P1024 error. I've ordered a k+dcan cable to be able to run Inpa/ista, so hopefully I can get some more detailed diagnostics and run the relearn function that others seemed to have had success from. I do also currently have the dreaded handbrake, TPMS and DSC amber lights up on the dash, but i'd be surprised if the two were linked

Went to try and start the car after it sitting for a couple of hours and it won't start. It cranks but won't fire.

Just wondering if anyone else has ran into the same error ,or similar, and has any tips, hints or solutions.

Thanks in advance

 

[Roberltd2]

Hiya Ryanmcde,
Have you had any luck with sorting this out?
I can't offer much in the way of advice but I did have issues recently with a leaking cam cover gasket, erratic idling and smokey exhaust. This is my post on it: https://z4-forum.com/forum/viewtopic.php?t=140138.
I was getting fault codes 2A2E, 2A2F, 2A38, 2A32, 2A47 and 2A37.
In the end the engine management light came on so I drove it no further.
Replacing the valve cover gasket was the main thing which needed to be done as the old one had become brittle after 16 years of use.
I also replaced the eccentric shaft sensor which had become contaminated with the leaking oil, along with the seal in which it sits. The sensor is quite expensive for OEM quality (£145 from Autodoc) but it's peace of mind.
It also turned out that the membrane for the pcv system had also perished hence smokey exhaust & high oil consumption. Although these can be bought separately and inserted into the valve cover, my mechanic advised against it (from experience) and so it was another £350 for a replacement cover with seal (Febi-Bilstein 103099).
Having given the engine a good run to get rid of any residues, an emmisions test revealed all the readings to be "spot on" in my mechanic's words.
I found the engine and throttle response to be a bit sluggish for the first couple of days. Then, following advice on this Forum, I tried a throttle reset. Turn ignition on for ten seconds, turn off for ten seconds, turn on again for ten seconds again and start the engine (no foot on the accelerator).
The difference was like night and day and I'm happy to say that the car is back to it's old self again. So far so good, touch wood!
Anyway, whether any of this is any help to you or not, I hope you get the car fixed soon.
Cheers,
Robert.

 

[ryanmcde]

Hi Robert,

So I have managed to fix the issue, ended up being the valvetronic motor itself. Ended up getting a 2a38 - P1030 (sluggish motor) as well. When manually adjusting the motor using the 4mm allen key i could fell how crunchy the motor felt. Powered it up and compared it to other videos of the motor and I could see how much jerkier it was. Got the new motor delivered today and could instantly feel the difference when turning it. Put it all back together ran the relearn function through inpa and fired up first time and felt brilliant, seems to have more go to it than when I bought it. No more engine codes (at least for the time being) and looking at the values on inpa the valvetronic system looks to be working as expected. The old motor looked to be the original bmw one, I am tempted to take it apart to see what failed on it. Next on my list is a rocker cover gasket but thats a job for another day.