Throttle position sensor problems...?
 

HELP, my 97 runner 3.4L rpm's jump around kinda like it wants to shift, but doesn't. It is really speratic, and the check engine light won't come on. It has been into toyota a couple of times, and they can't find anything!!!!!! I have cleaned the MAF, replaced the plugs and put in a new fuel filter without any change. Could it possibly be the throttle position sensor, and if so, is there a way to test it without a computer code?

My 97 2.7 Tacoma had TPS issues, though mine was a 5 speed. What would happen to me was the truck would just skip every now and then. I would be driving dowen the highway and the power would cut right out for just a second. It was so sporadic and quick that I never got the chance to see what the tach was doing as it skipped. Once I replaced the TPS I never had another problem. The TPS was only $60, so if you can't test it just buy a new one.

Here is some info on the older models, I don't know if they are the same or not. http://www.4crawler.com/4x4/CheapTricks/TPS/index.shtml