Issue:
My dodge neon started to accelerate by its self and stays accelerated.
My breaks can barely stop it. The check engine light is one. and it says it’s a pinched solenoid sensor for the emissions. But to my knowledge that won’t cause my car to accelerate like crazy and remain accelerated to 40mp and remains there.

I did some reaserch and i keep comming up with IAC valve (Idle Air Control Valve). Not sure if this is the problem.

There could be numerous problems.
If anyone might now. please let me know. Im replacing IAC valve this week.

I repalced the Throttle Position Sensor. and still not fix.. i havent replaced the IAC valve, it has to be special order. so im waiting on it.

I had one where the vac hose for the power brake booster came off. Not only did it make the engine race but the brakes didn't work very well.

I did three things and then i got it to work.

1. I checked the vac hose for the power brake booster & everything was good, secure and tight, but the problem was not fixed.

2. I reaplced the Idle Air Control Valve and problem was still there.

3. I reaplaced the throttel and now it works. Not only my car runs normal, but it runs better. Runs line new.

Actual problem: The flap in the throttel was stuck in open position.
Solution: I replaced the Throttel