yes
yes they do go bad
Look in your owners manual and it will tell you under scheduled maintanence. It should be around 90,000 to 100,000 miles. The AC Delco plugs should be used as your replacements.
Spark plugs and wires
Every gas burning internal combustion engine has spark plugs. Diesel engines do not. Your Impala is not a diesel, so it has plugs.
For BEST performance you should exactly what came in it and that is AC Delco.
Look in the fuse box, it's the round silver thing that plugs in.
Remove the spark plug wires from your 2000 Chevy Impala spark plugs. Remove the spark plugs with a 5/8 deep well socket by turning the socket to the left. Reverse the process to install the new spark plugs.
I recommend AC Delco which is the same as was put in it at the factory. You will get longer life and better performance.
need to know what engine size and year 3.5L 2006
unplug the wires and swap, its very simple. plugs are located on the left side of the engine, to the right of the battery.
Loosen the 2 dog bones on the front of the engine and pull the motor forward to get to the back plugs.
For best performance and mileage you should use the same plug that the manufacture intended for it and that is AC Delco. The parts house will tell you the proper gap.