Re: 02 check light
It is a good idea to have the trouble codes that are set on the vehicle's computer, retrieved from it. Most auto parts store will offer this scan for free. These codes explain what circuit is sensing the problem, but not exactly what the problem is. So, if your get a code for, random misfire detected, it doesn't mean the spark plugs, and wires are at fault. It could be caused by a vacuum leak or even a coolant leak. The recovered code will most likely be for rich exhaust or lean random misfire from the oxygen sensor. An O2 sensor may not be the problem. Ford uses a throttle air bypass valve/TABV also known as an Idle Air control/IAC valve. This is a computerized choke that can get carbon built up causing it to stick open or closed. When it sticks open, it will cause a lean misfire and when it sticks closed it will cause the engine to load up on fuel, which can make the engine hesitate on acceleration and a rich mixture. This TABV/IAC is a serviceable part that can be removed, cleaned with a throttle-body cleaner that is O2 sensor safe and reinstalled using a new base gasket.