Originally Posted by RPM90
I'm curious, why are they changing the exhaust valves to fix a ticking sound caused by the hydraulic valve lash adjusters?
Did they do a cylinder pressures leak down test, that showed your exhaust valves are worn and not seating/sealing properly?
Per BMW, they can change the valve adjusters.
Why new exhaust valves?
As far as this ticking sound, in general, hydraulic valve adjusters commonly makes noise. And, in most of the cases it's not detrimental to the engine.
The ticking noise is often heard on cold start due to oil pressure needing to build up and pressurize the adjusters. Until the oil pressure goes up, and the oil thins enough so that it can enter the very small oil port to pressurize the adjuster, there will be a ticking sound.
Also, many times people misdiagnose their own engines by confusing injector tick from valve adjuster tick.
BMW isn't going to do a general recall as the NHTSA is not likely to issue a recall on a mechanical issue that is not related to safety. NHTSA doesn't do recalls for those types of issues.
BMW can issue an in house "recall", which they have, and it's called a "TSB". It's on a as-needed basis. If a customer comes in with a problem, the tech will use the TSB to see if it can address or fix the problem.
If the vehicle is under warranty, or the problem was documented during the warranty, then BMW will fix the issue.
This is why it is VERY important for those of you who suspect a valve lash adjuster problem, to report it to your dealer and have them document the issue during your warranty. If later it is determined that there is a problem that has a fix, you will have a remedy even after warranty.
It would be very hard to confuse an injector tick with a valve tick. When it's the valves it sounds like a little hammer (ok medium size hammer) inside your engine tapping. Also the TSB says the exhaust valves were actually a possible defective valve part number (case by case basis). Since I have had mine replaced my car has done some ticking again. My suggestion if you live close to work take the long way so your oil will fully heat up (especially in the winter) and do as the manual says and not let your car sit and idle to warm it up in the morning (even in the winter) my 128i only ticks when...
A)I don't drive far enough to warm the engine up before shutting it back off but will not tick until I turn it on after a few short trips
B)I let it sit and idle for a few minutes after starting it up in the morning
Most people will tell you to not drive right away as soon as you start your car up on a cold morning. My engine doesn't seem to tick ever since I have been just driving off right after start up. (My engine tick also would speed up with the engine RPMs. I would have been able to notice the ticking if it was there.)