Rhinosoft

Hello all. I am currently having a difficult time diagnosing a problem with my acceleration in my 2003 GX470. 1 out of every 100 times i will start the car and attempt to accelerate but the rpm's will go up to five thousand and i will not move very fast until 2nd or 3rd gear. Every other time out of the 100 it runs fine. Any suggestions? And forget about the drive shaft issues in this car. Its like riding a bull!!!