The E46 M3 VANOS system is one of the weak spots on an otherwise fantastic engine. The VANOS is BMW's variable valve timing system that changes camshaft timing to boost low end torque without losing top end power. It's critical to enjoying the S54 engine to its fullest. VANOS failures and rebuilds on the E46 M3 are common and this fully rebuilt and upgraded unit from Dr. VANOS is the best one out there. To really understand the shortcomings and weak areas of the E46 M3 VANOS system you have to be specialist and no one understands the VANOS system better than Dr. VANOS. Not only is this a rebuilt VANOS unit but several enhancements and upgrades are built in so you get a VANOS unit that functions better than the original and will last longer.
Dr. VANOS S54 Features (included with every unit) -
- New OE BMW solenoids
- New solenoid valves and high pressure oil regulator
- CNC modified oil pump disc for exhaust hub
- upgraded piston seals
- VANOS housing profile gasket
These upgrades significantly improve the operation and longevity of the E46 M3 VANOS unit, which means better performance too! Additional upgrades are also available to further improve the complete system (see below).
VANOS (or VAN0S) is BMW's variable valve timing system. The VANOS unit is basically a pump and solenoid that rotates the camshaft to make more torque at various RPM. Having a variable camshaft means the M3 S54 engine can make a lot of power in the high RPM without feeling too sluggish in the lower RPM. Obviously any problem with the S54 VANOS unit will have a major effect on performance and drivability, including misfires, fault codes, rough running, sluggish performance, poor fuel mileage, and the dreaded "marbles in a can" rattle sound.
The S54 VANOS is made up of three major parts: the adjuster units (1 for each camshaft), solenoid pack, and the oil supply and pressure system. The part on this page covers all three. Typically, the adjuster unit 80-100,000 miles. The solenoids that drive the VANOS adjustment unit are the first to need replacement, usually by 60,000 miles. They will most often be associated with "VANOS jammed" fault codes. The solenoids can be replaced independent of the complete VANOS unit, although new ones are included with a complete VANOS unit like on this page.
The telltale rattle of VANOS failure is not always the best indicator of a VANOS issue, especailly on the noisy S54 engine. In addition to the VANOS, other parts make similar noises: valve rocker arms/tappets, timing chain, and timing chain guides. A BMW specialist shop should have more advanced tools that can tell which part of the VANOS needs replacing. It's not uncommon for high mileage S54, especially if service was ignored or deferred, to need more than just the VANOS unit replaced. Other wear items or weak areas include the bolts holding the sprocket to the camshaft, the hub on the exhaust camshaft that drives the VANOS oil pump, the aforementioned chain guides and valve adjustment, an VANOS oil lines. All of these parts are available separately.
This item is a complete S54 VANOS unit rebuilt by Dr. VANOS - the leading VANOS specialist in the world. It comes with a one year warranty. The price shown includes a refundable $400 core charge.
A core charge applies to this purchase. The supply of original parts for rebuilding keeps the final purchase price low. The core must match the part that was supplied in terms of fitment, type, application, accessories, and hardware. Damaged or modified cores will not receive a refund. A core charge can only be refunded once the core has been inspected and approved. Click here for our Core Policy
BMW Fitments: 3 Series
E46 (99-05) > M3Z Series
E36/7 / E36/8 Z3 (96-02) > Z3 M - S54Z Series
E85 / E86 Z4 (03-08) > Z4 M