Chevrolet Repair: throttle position sensor

Question
Hi I just replaced my TPS on my truck. The other day in the morning it would not start. So after work I was messing around with some connections and guess I must of unplugged it. Well the truck started rite up. Som I went and bought another one but the truck still wouldnt start. So I went and returned it and bought another one at a diffrent auto parts store and to my disbekief it still did not start. When Im disconnect it it starts but runs a lil rough and at a lil higher rpm. What am I doing wrong? Its a 1997 chevrolet pick up 3500 with a 454 vortec engine

Answer
HI CHARLIE,A TPS SENSOR SHOULD NOT STOP THIS FROM STARTING...IT HAS TO BE A FLUKE THAT IT DID START LIKE THIS...YOU NEED TO CK FOR FUEL OR INGNITION [SPARK] YOU ARE MISSING SOMETHING..THIS MAY HAVE A PROBLEM WITH THE WIRING HARNESS THAT IS CAUSING THIS..SOMETHING SHORTING OUT TO THE TPS SENSOR..CAN YOU GET THIS SCANNED AT A SHOP FOR DATA OR FAULT CODES [EVEN IF THERE IS NO CK ENG LIGHT ON]...THIS HAS A OBD2 SYSTEM...THIS MAY SHED SOME LIGHT ON YOUR PROBLEM..LET ME KNOW HOW THIS GOES..GOOD LUCK,,TOM