One problem related to timing tensioner has been reported for the 2005 Chevrolet Impala. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2005 Chevrolet Impala based on all problems reported for the 2005 Impala.
175555 miles fuel smell and fuel loss when car is running. Rough start, some missing. Fuel filter failed at filter inlet spraying gas onto underbody of car so didn't see the fuel spill. Replaced filter and o rings. Squealing belt sound at start up. Serpentine belt tensioner broke, replaced tensioner and belt. No check engine warnings, no electronic gauges I have the basic Impala model. Watched the fuel gauge drop by lines while driving and smelled gas when shut off car. Fire hazard, and engine failure if the belt broke completely. . Another 300$ spent.