I am having a problem with my son's college car. Throttle sticks wide open and will not slow. This problem is intermettent. It apears to be random in when it starts and random in when it stops. Have had it in the garage 3 times and it did it one time for 5 minutes and stopped before the mechanic could figure it out. No codes have helped to identify the problem. This is a huge saftey issue when it starts racing while driving. We have not been able to determine what sets it off. The trottle has been cleaned and we have been told it seems to be ok. My understanding is their is a motor that controls the trottle on the Neon and imagine that complicates the potential causes. The garage is hesitant to start changing things out as it might take hours to see if the problem has been resolved.
A typical event starts at highway speed. Traveling 65 MPH. Let off on the peddle and the engine speed remains at the max speed it was at. If he puts it in neutral and pulls over the engine continues for several minutes at the high speed and then will eventually slow to normal. Following this event is a period where it is more likely to happen more but at less dramatic speeds. This might happen a half dozen times. When it stops, it might take a week before it happens again.
Please help. The car is 11 years old but only has 50K on it. Plenty of life left. Thanks in advance for any thoughts.