Please choose the correct ending to complete the given sentence: Computers and Electronics: [header] How to tell if a timing belt tensioner is bad [title] Listen. [step] A bad tensioner will usually be accompanied by noise. This noise could be some type of squealing or rattling coming from the timing cover area.

Ending1: On a bad tensioner, air pressure may try to penetrate through the inner shell to cause loose or unfixed parts of the belt to crash. [title] Make sure your timing belt is closed in a sealed chamber. Ending2: Also, when your timing belt is loose, it will cause some drivability issues usually under high load or high rpm. If your timing belt is not properly tensioned it will not keep the valves timed properly to the lower end and this will cause misfires, loss of power, bucking, and could even cause a no start condition. Ending3: To hear any further sounds you may need to listen to your belt. [substeps] Without warning, call attention to any loud grating. Ending4: [title] Look for cracks on the belt that can cause interruptions to the operational timing process. [title] Check for cracks in the belt threads.

Answer format: ending1/ending2/ending3/ending4