Transmission Problem??? on 2000 Nissan Maxima

1st time a couple of months ago and 2nd time just his weekend, on really hot Florida days I will be driving along and go to accelerate and nothing happens. I depress the accelerator and I can watch the tach go up but the car doesn't accelerate it just cruses along at the old speed it was going, repeat an get the same thing. The last time I experienced this I pulled over shut off the engine, waited a couple of minutes, started it back up and it ran as though nothing had ever happened. All trans fluids are good. Auto Zone pulled two codes: #720 Speed Sensor and #138and #139 O2 Sensor. THANKS!

Asked by for the 2000 Nissan Maxima
The speed sensor code will definitely be a problem for your transmission, so get that replace ASAP. Code P0720 is the Vehicle Speed Sensor which measures the RPM of the tail shaft of the transmission, which s very critical for the proper operation of the transmission. Also, replace the Oxygen Sensors, before you ruin your Catalytic Converters.
Thanks! I was affraid that the only thing that the Speed Sensor did was talk to the spedo and not much else, and that it wouldn't really have much effect on the operation of the transmisission itself. Do you know if it's accessable on this model without putting it up on a rack?
Response to the code po720 is the out put sensor(also call revolution sensor),its function is to pick up the revolution signal from AT through TCM to guild the gear change,but don't max up with other call vehicle speed sensor.these are complete different sensor and belong to different system.The VSS function is pickup the signal from AT and sent to speeddmeter and odometer.Malfunction will show no speed in that meter.