2001 Chevrolet Impala • 6 cylinder 2WD Automatic • 170,000 miles

We have a 2001 chevy impala, while idleing at red lights or in traffic it will stall, exhaust is uneven and there is a loud tapping sound coming from the engine which gets loader when u accelerate. What could the problem be?
February 3, 2011.

As far as the idle, check for vacuum leaks. Also, check the idle air control valve. If the check engine light is on, have the computer scanned. Most parts stores will do it for free.

The noise could be many things. A knock can be caused by a engine bearing, belt driven accessory. You need to locate a more specific area that it comes from.