occasionally will not shift up and revs high.

Is it possible its a solenoid in the transmission. Is a tps easy to diagnose/fix

With a 'scanner' it is!.... Throttle Position Sensor has major influence on trans shift and throttle response!... Needs to be tested with a scanner so live data can be viewed for TPS signal range.... This is one likely scenario and others certainly exist!... In any event it needs to be scanned with a real scanner!.. That is the only logical way to fix this....

Just wanted to thank you for your help and advice. Took a chance and just replaced the tps and it seems to have solved the problem. Running on highway at lower rpm. Runs smoother. No more hesitation or bogging. Much appreciated!

Glad to hear it!!..... Sometimes you get lucky!.... I always have to TEST everything, but then that's my job!! .. That would have been my first 'guess' as I have repaired that problem before..... After testing!... Thanks for the feedback!!!... Other owners read these responses, so I hope they can benefit also...