ICE Ran at high RPM for no apparent reason

I had switched off the car after driving it for 45 Miles. I was gone for less than 5 minutes. I started the car again with water temperature about 178 F.

ICE came on after usual 7 second delay as I started the car. It did not have to come on still as ICE was warm. But anyway that is not the matter. What was Unusual was ICE was running at 3400 RPM even when I was rolling slowly with foot off of pedal. ICE still continued running at this high RPM. Car was rolling the usual way it does and responding well to pedal input. It was not the mat getting stuck under the pedal as is reason for recall. Mat was perfectly fine anchored in. ( I have now taken it off.) SOC at this time also was around 64. So low battery also was not the reason for ICE to run.

Lifting foot off also did not help although the car did slow down. This kept happening for couple minutes until I finally approached some downhill slope and then finally ICE switched off. Car was driving fine all along though. Nothing unusual.

I had similar experience one time before in my driveway. That time switching the car off and restarting resolved the issue. I did not do that this time since I was on the road and car was driving fine.

After this incidence car is driving fine with ICE working normally.

Any reason why this should happen? Anyone else had similar experience? Is it some sort of software bug that occurs only under specific situations?

I am not overly concerned. I bought this car used 5 months back and have driven it for over 12000 Miles. Also the car was driving fine even with ICE revving up. And after this incidence it is now working perfectly Normal with ICE coming on at usual RPM's as required.

Any thoughts?

 

Thanks. Certainly a point to consider. I will definitely have throttle body cleaned. I don't know though if I will know for sure since the problem just happened twice.

Difference in my case is my car did not have any uncommanded acceleration issues. It was driving just fine. Just that ICE was running at high RPM for no apparent reason.