MultiAir

📖 YOUCANIC Automotive Glossary

MultiAir is Stellantis/Fiat Chrysler’s electrohydraulic variable valve timing and lift system used on many Fiat, Alfa Romeo, Jeep, and Chrysler engines. Unlike traditional cam-phaser VVT that only adjusts timing, MultiAir uses a hydraulic chamber between the camshaft and the intake valve — a solenoid controls the oil in this chamber, effectively decoupling the valve from the fixed cam profile. By controlling when the solenoid opens and closes the hydraulic circuit, the system can vary both valve lift and timing independently for each cylinder, providing benefits similar to BMW’s VTEC and Valvetronic combined.

MultiAir issues include ticking noise from worn hydraulic lash adjusters (sometimes called MultiAir brick failure), oil consumption from worn valve stem seals (exacerbated by the system’s high oil demand), and rough idle from solenoid or actuator faults. Regular oil changes with the correct specification oil are critical. The YOUCANIC UCAN-II reads MultiAir-related DTCs on supported Stellantis vehicles.