BMW N52 - Hydraulic Valve Adjuster Problems

Hydraulic Valve Adjuster Problems

The ticking noise of Hydraulic Valve Adjuster is a known problem with the N52 (3.0L) engine fitted with manufacturing date prior to November 2008. An occasional ticking or rattling noise from the HVA elements may occur during cold engine starts or frequent short-distance driving, recently known after the engines reach 50.000 miles. In these situations, the HVA elements may not yet have been supplied with sufficient amounts of air-free oil. This condition will not cause any damage to the engine, and usually remedies itself with a longer driving distance or operating times at full operating temperature. BMW dealers' first response is to perform HVA bleeding procedure, however this procedures seems not to resolve the matters. The second attempt to solve this problem is a replacement with improved HVA parts, however this procedures also does not fully adress the problem. Finally, a newly-designed cylinder head replacement solves the ticking noise problem for vehicles under warranty. Vehicles produced after November 31, 2008 have already been fitted with improved cylinder head that resolves this HVA problems.