The symptoms are a starting problem, for example you may get in the car, drove 30 miles, turn the car off and now it won't start for love nor money. It may need a throttle body service.
Here's what you do: get a can of spray carb cleaner. Take off the air cleaner and spray half the can into and around the intake. Open the butterfly if there is one and spray all around it. Douse everything in that stuff.
Wait for 20 minutes.
Now start the car. If this was the problem it will start. Now empty the other half of the can into the intake while revving the engine.