Knocking noises are not related to tune-ups, and tune-ups don't involve much anymore. Spark plugs, spark plug wires on some cars that still use them, and a few filters is about it.
For the knocking, if it's coming from the engine, you have much more serious trouble. If it's related to the steering and suspension systems, that can be identified with an inspection at a tire and alignment shop.
Friday, July 1st, 2011 AT 7:04 AM