What is the purpose of the camshaft timing belt or chain and what wear indicators could lead to valve-to-piston interference if timing fails?

• A. It times the opening and closing of the valves relative to piston position. Signs of wear include stretched belt/chain, missing teeth, noise or timing drift, and potential valve-to-piston interference on interference engines if timing is lost.
• B. It regulates fuel delivery timing to cylinder head. Wear indicators include worn cam lobes and misfiring spark plugs.
• C. It controls exhaust gas recirculation and reduces valve timing.
• D. It regulates ignition timing using a distributor rotor.

Answer: (A)