I have a 1993 V6 3.0L 3-VZ-E 4x4 auto 4-runner w/170,000 miles. I was driving at ~30mph when the rpm's started to go up without any increase in speed, stay there for a while and then all of a sudden go down. This up/down continued all the way home. Any ideas? Thanks!

 

it could be a dead spot in your tps

 

search for a thread on how to test the TPS....it also could be other things

 

maybe the transmission slipping?

 

tps for sure...
same thing happens to me
the bolts on the tps where loose
check that first ..........

 

Happens when you are in gear with no increase in road speed? Your trans is slipping.

 

Have a tach? How far "up" did the RPM's go?

Checked your trans fluid recently?

 

Do you mean the RPM gauge moved up and down or that you felt/heard the RPM increase?

 

This is going on in my girlfriends 91, she has a 22re, it stops surging when we unplug the TPS.
It's funny because when she's in first gear going threw parking lots and it decides to surge, it look like she has never driven before.