The throttle body is the part of your car which controls and regulates the amount of air that goes into the engine. It is of course controlled by your foot on the pedal, or an internal mechanism if you have cruise control enabled.
The throttle body essentially comprises a large valve, through which air is allowed to flow. When you put your foot down on the accelerator pedal, this opens the valve to a certain degree, allows the air in, which gives power to the engine. Simultaneously, sensors will detect the amount of air flowing into the engine, and combine this with fuel in order to achieve the correct air to fuel ratio. The further you depress the pedal, the more air that goes in, and the more power the engine produces.
All fuel injected cars are fitted with at least one throttle body, but some may be equipped with more for better response when you put your foot down. A good such example is the BMW M3, which actually has one throttle body for each of its cylinders.
Throttle bodies can sometimes fail, or become impaired. Often this is because the valve has either lost its ability to easily open and close, or the area has become clogged with deposits. When this happens, the problem needs to be fixed immediately. The first signs of issues with the throttle body often come when first pulling away in the car. If the valve does not open as much as you’d expect it to when you put your foot down, the car is likely to stall. Similarly, it is often said that cars with faulty throttle bodies have uneven and ‘lumpy’ acceleration. As a result of this, fuel economy and all-round performance can be extremely poor.
Fixing a faulty throttle body can vary. Sometimes, all the unit will need is a clean, to allow the parts to operate smoothly as they should. In other cases, the whole unit may need to be replaced. If you’re looking to bring the costs down, you could buy the part yourself click here to visit www.worldcarparts.co.uk, where you’ll find a throttle body for most cars.