PLEASE HELP? 98 wragler missing out

My 98 Jeep Wrangler is having problems missing out (especially when going up hills, or when vehicle is under load). It has the check engine light on, and I have had it read. The code is P0123 which in the manual says that the Throttle Position Sensor is above the accepted voltage. In the manual it says that in order to test the TPS you use a digital volt meter, and the center terminal (output) should put out voltage of greater than .350 millivolts but less than 900 millivolts. I replaced the sensor, as the original one was generating output of greater than 1000 millivolts, but the new sensor also generates output of greater than 1000 millivolts and didn't seem to make a difference in the way the Jeep runs.

Other than a defective TPS, what could cause an excessive output voltage from the TPS? Also any ideas on what I should try to get my jeep running smooth again. Thanks for any help, and sorry for the length of the message.....