Tip - How to Bypass the Knock Sensor on a 1990 Ford F150 | eHow

The knock sensor on your 1990 Ford F150 helps to protect the engine from engine knock. Engine knock---or "knocking"---is the result of improper combustion in the combustion chamber of your truck. Usually this is the result of improper timing and ignition. Knocking, if left unchecked, can damage your F150's engine. However, if you are experienced in...