Valves and lifters function as part of a vehicle’s valve system. Valves open and close, allowing compression for the power stroke and the release of exhaust gases. Valve stems can stick either permanently or sporadically, due to heavy varnish on the valve stem or weak return springs. Lifters control the valve movement up and down. Without doing major repairs to the engine, a vehicle owner can try a few simple mechanical procedures, or he or she can a use a specific additive to cleanse and lubricate the parts.
How to Cure a Sticky Lifter or Stuck Valve
Set the vehicle in park and engage the emergency brake. Start the engine and raise the hood. Allow the engine to reach operating temperature.