The VANOS system found on BMW’s M62TU V8 engine provides continuously variable valve timing for the intake camshafts only, with one VANOS unit located on each cylinder bank. Unlike BMW’s Dual VANOS inline-six engines, the M62TU’s exhaust camshafts remain fixed while both intake camshafts are adjusted simultaneously through a range of up to 40 degrees of crankshaft rotation. The DME controls a PWM-operated solenoid on each bank, which directs engine oil pressure to either side of an internal piston and helical gear mechanism to advance or retard intake camshaft timing. By continuously adjusting the intake cams according to engine speed and load, the system helps improve low- and mid-range torque, idle quality, fuel efficiency, emissions, and overall drivability. The M62TU VANOS units are integrated into the intake camshaft sprockets and are also known for developing seal wear and internal mechanical wear, which can contribute to reduced VANOS performance and the characteristic startup or operating rattle associated with aging M62TU engines.
