Engine makes sounds as if accelerator is pressed even when it isn't on 1999 Honda Accord

When I am idling, the engine thinks that I am pressing and letting go of the accelerator even when I am not.

Any ideas? Thanks

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2 answers
Could be a sign that the car is low in coolant (low in coolant drives the engine coolant temperature switch nuts), could also be a problem with the idle speed control.
This could be a problem with the throttle position sensor, but it is potentially dangerous, so I recommend taking the car in to a shop and having it address immediately. If this were to happen when you are not stopped, you could have an accident.