2000 Mazda Protege

I have a 2000 Mazda Protege with an automatic transmissson. The car has 65, 000 miles on it. Last week, while driving on the highway (65 mph); the car shuddered, as if it got rear-ended. The engine revved up for about 3 seconds. After that, it ran as normal. The check engine light did not come on. Any ideas on what could be causing this?

If the car revved up while going down the road in gear, sounds like a transmission problem. Check the fluid for level and condition. If it doesn’t happen again count your lucky stars.