Random acceleration

Over past year my dughter’s car (Honda Civic 1997 LX,air, cruise etc)would accelerate randomly. It happened about 5 times so far. It has been inspected twice by Honda dealers and once by another shop, nothing found. Highway driving with air conditioning ON over long distances, not a problem. When this problems occurs the following conditions are present:

Hot, sunny day

Air conditioning ON in STOP and GO traffic (traffic jams)

The RPMs will start gradually to increase over a few minute time span, and will climb up to 6000 RPM and will stay elevated until you pull over and shut car off

It becomes difficult to stop the car, breaks get hot, if you don’t pull over after a few mintues of this, car will BARELLY stop, once it happened in a school zone and she had to run the stop sign because breaks failed to stop car

Takes long time for car to cool down, and if you do not give it enough time to cool down will rev up again when turned on



Throlle cable and floor mate don’t seem to be the problem, cruise control not engage. Car drive normally no other problems. I would like to sell but would like to fix problem before selling. I would greatly appreciate any HELP.