Renhard

I have an acura rsx type s 2004.... Bought the car used..... this is the second time this is happening....

First time I was coming on the highway, pulled away from the toll booth and while in second gear in vtech zone i see the speedometer drop to zero and wont move, vtech then cuts, and i get locked out of 6th gear..... first thoughts is that my speed sensor is gone and I should replace...... went home and check my fuses and pushed down the wire on the speed sensor, trying to find any reason why it just stop working... was trying to pull the sensor but was difficult with the tools I have and lack of space, so I no longer pulled it..... left the car park for 2 days.... needed it to go work so i decided i would drive it but conservatively because i know vtech wont work now.... start the car, drive down the road and there and behold it is working again thought then that if it is the speed sensor itself, it wouldnt just come back like that.

Second time: Two days ago driving to work and this car over take me then started to drive unbearably slow, way under the speed limit.... decided to overtake, was in 2nd gear and once again in the peak of the power somewhere between 7000 and 7600 rpm, the speed sensor cut again. stop working for the entire trip to work.... parked the car for about 3 hours before time to leave work... Leaving work it started to work again.....

What could be going on and why did it only occur at high revs???

Please help