Vehicle Compatibility Information For Ford Focus 2000-2002 L4 2.0L Automatic Transmission, DOHC What is a throttle body ? The throttle body is the part of the engine that mixes air with the fuel to allow combustion to take place. When a throttle body gets clogged with carbon, the vehicle may suffer from issues ranging from a lack of fuel mileage, loss in efficiency or may even become totally inoperable. When you need to replace the throttle body: 1. Check engine light and/or reduced power warning light is on. If the check engine light or reduced power warning light comes on, a mechanic will determine if any of the stored trouble codes implicate a throttle body malfunction. .
