This post is to make owners of 2.5i, 2.5si and 3.0si Z4's about a known issue with the N52 engine (so also affects 3 Series etc) and the HVA's (Hydraulic Valve Adjusters)
I have collected my car today from the dealer after having a complete new Cylinder head and internals replaced at a cost of over £3400 (Luckily under Warranty).
The issue is that when starting the car from cold that the Hydraulic Valve Adjusters do not fill with oil as required making the car sound like a very bad diesel or Trabant. I have been able to drive 2-3 miles without the noise showing any sign of disappearing.
I first suffered with the problem nearly 2 years ago when the car had covered only 2k when BMW Assist were called out who carried out the Bleed Procedure I have since found out. Now with 20k on clock it happened a few times recently, most of the time when collecting from the dealer for some strange reason, but made it easier to get sorted, although dealer had to go through the "PUMA" process with BMW to get this sorted. This is the first case my dealer has come across.
The following youtube video I found shows the problem very well
[youtube]tjGdBmgVDuE[/youtube]
And the following 42 page forum thread gives a bigger idea about the problem.
http://www.e90post.com/forums/showthread.php?t=13504
Receipt showing items replaced and costs. (Names etc removed to protect the innocent).
The New Cylinder Head has been redesigned to include a non return valve to keep the oil in the lifters when the engine isn’t running to avoid this issue.
If you use your Z4 daily the issue may not appear, I use mine every other day during the week there are odd weeks where it is not used at all, it is after these period the problem is most likely to happen as the oil has had more time to drain.
I have tried to keep this short but can provide a lot more info if required.
Steve
I have collected my car today from the dealer after having a complete new Cylinder head and internals replaced at a cost of over £3400 (Luckily under Warranty).
The issue is that when starting the car from cold that the Hydraulic Valve Adjusters do not fill with oil as required making the car sound like a very bad diesel or Trabant. I have been able to drive 2-3 miles without the noise showing any sign of disappearing.
I first suffered with the problem nearly 2 years ago when the car had covered only 2k when BMW Assist were called out who carried out the Bleed Procedure I have since found out. Now with 20k on clock it happened a few times recently, most of the time when collecting from the dealer for some strange reason, but made it easier to get sorted, although dealer had to go through the "PUMA" process with BMW to get this sorted. This is the first case my dealer has come across.
The following youtube video I found shows the problem very well
[youtube]tjGdBmgVDuE[/youtube]
And the following 42 page forum thread gives a bigger idea about the problem.
http://www.e90post.com/forums/showthread.php?t=13504
Receipt showing items replaced and costs. (Names etc removed to protect the innocent).
The New Cylinder Head has been redesigned to include a non return valve to keep the oil in the lifters when the engine isn’t running to avoid this issue.
If you use your Z4 daily the issue may not appear, I use mine every other day during the week there are odd weeks where it is not used at all, it is after these period the problem is most likely to happen as the oil has had more time to drain.
I have tried to keep this short but can provide a lot more info if required.
Steve
