What is a throttle body, and why do I need one?
I took my 1993 Mazda 626 for its annual state emissions inspection, but the garage couldn’t perform the diagnostics because the car was idling too fast. I then took my car to the dealer and had them check out the idle. They told me that my throttle body was shot, but they could get me a new one for $1,000. However, they were able to adjust the idle so I could pass the emissions test. My car seems to be running fine. So, I ask you again, what is a throttle body, and why do I need one? — Cathy Ray: The throttle body is the throat through which the air passes when you step on the gas pedal. And it costs $1,000 because it’s a finely crafted and machined piece of. . . well, cheap aluminum. Tom: What happens to them is that the throttle plate, the steel “flap” that lets air in, wears a groove into its aluminum housing or “body.” And when that happens, too much air is allowed to get through, even when the throttle plate is closed. So it’s as if you have your foot lightly on the gas pedal, ev
