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?

 

you could take it out and try to clean it, i might just be getting stuck a little. when I had to replace mine, the CEL came on a few times, and I was having really bad idling problems.. don't know about the shifting problems though, I have a manual tranny.