HIGH idle

[toysupra14]

Well acutually if I don't try and turn the jeep off it will redline. Ok I just put banks headers on and am now trying to get it to a exhaust shop...so I am running headers only. I got the codes P0123 and P0505 so I am just wondering if any one else has started their jeep and the rpm's go up till it red lines. BTW its a 2000XJ 4.0 AW4 NP231 w/o the extra converters.

Thanks
Kevin

[scoobyxj]

P0123 Is Throttle Position Sensor Voltage High... Throttle position sensor input above maximum acceptable voltage
P0505 Is Idle Air control motor circuts... SBEC-II

Better check the TB electrical connectors to make shure they are all plugged in, and solid. Also make shure you didn't nick any of the wires.

[langer1]

Those codes usually mean the Ground for those circuits are open.

[toysupra14]

And do they ground through the block or one of the wires going to them?

[langer1]

And do they ground through the block or one of the wires going to them?
They have a ground wire.

http://img.photobucket.com/albums/v11/langer1/jeep/FSM/TPS-TCU.jpg

[jeepr]

air leak will also red line the motor. Like if you didn't get the intake flush with the block, or o-rings on the injectors.