Cadillac Repair: 93 Cadillac STS 4.6L, throttle position sensor, tps harness

Question
My STS has the Northstar in it. Just recently it has started rough idle and sometimes it won't even idle. If it does idle when you shift into drive it tries to die and sometimes stays running.When you drive it, when it gets into second gear it starts jerking and shifting into other gears I guess.The code that showed up is P021, which is the Throttle Position Sensor Short circuited. I have just replaced the tps and the same code shows up. So do I have a bad wire somewhere? If I do can I find it easily?
Right now the TPS is just disconnected because for some reason it runs fine that way.

Thanks

Shane Schrick

Answer
Hi,Shane

The TPS harness could be shorted or open,this harness runs from the throttlebody to the engine harness that lies over the transmission bellhousing,i would check the terminals and the wires at the TPS connector first,they usually get open at the connector,if the wiring checks good you may have a failed PCM.

ED