99 Jeep Cherokee Sport 4.0

I replaced the throttle position sensor and the idle air control valve. The IAC came with an o ring. The throttle position sensor did not. The old TPS also did not have an o ring.

So, is the TPS supposed to have an o ring or a gasket? Also, I still getting codes P505 and P123. Can a missing o ring cause those codes?

Thanks.

 

The TPS doesn't have a gasket or o-ring, BUT it has a seal on the shaft that fits over the throttle shaft. I ruined a TPS by spraying Seafoam down the throat of the throttle body and getting it into it. ALWAYS put Seafoam into a vacuum port instead of using the can instructions that say to put the hose into the intake ducting.