The invention relates to an improved system of electro-mechanical hydraulic valve lifters for piston engine automobiles that increases fuel economy and reduces fuel emissions. The electro-mechanical hydraulic valve lifters contain that enclose a magnetorheological fluid chamber, containing magnetorheological fluid. A control module manages voltage sent to the magnetorheological fluid in the magnetorheological fluid chamber. The control module introduces various amounts of magnetic flux to the magnetorheological fluid in the magnetorheological fluid chamber. The magnetorheological fluid's viscosity changes based on the amount of magnetic flux applied to it from the electromagnets and, along with the magnetorheological fluid chamber spring, controls how much an intake and exhaust port of the spark plug engine opens to control the amount of fuel used and exhaust let out of the engine.

Methods and systems are provided for performing fuel vapor canister purging operations during engine off conditions. In one example, a method may include, responsive to an indication of breakthrough of vapors from a fuel vapor canister during engine-off conditions, configuring a first cylinder with both intake and exhaust valves open, opening a canister purge valve, and applying air pressure to the vapor canister such that desorbed canister vapors may be routed to an exhaust catalyst, the exhaust catalyst temperature maintained above a light off temperature. In this way, during engine-off conditions, including conditions wherein a vehicle is powered solely by battery, bleedthrough emissions may be reliably reduced by purging the vapor canister to the exhaust catalyst without requiring turning on the engine.

Methods and systems are provided for performing fuel vapor canister purging operations during engine off conditions. In one example, a method may include, responsive to an indication of breakthrough of vapors from a fuel vapor canister during engine-off conditions, configuring a first cylinder with both intake and exhaust valves open, opening a canister purge valve, and applying air pressure to the vapor canister such that desorbed canister vapors may be routed to an exhaust catalyst, the exhaust catalyst temperature maintained above a light off temperature. In this way, during engine-off conditions, including conditions wherein a vehicle is powered solely by battery, bleedthrough emissions may be reliably reduced by purging the vapor canister to the exhaust catalyst without requiring turning on the engine.