The P0118 indicates an unreasonably high signal in the CTS circuit (no pull-down resistance from the sensor). This occurs when the CTS fails in an open circuit mode, or the CTS is disconnected, or the circuit between the CTS and PCM is open.
The transmission range switch is mounted to the outside of the transmission, on the top of the transaxle at the left rear corner:
The transaxle main electrical connector is at the front of the transaxle. These connectors in earlier models had a tendency to work loose, and there was a modification to add latches in later revisions to prevent this. You should be able to see it here (
image courtesy of BNaylor):
Given that multiple transmission codes exist, this connector is suspect. If the connections are not reliable, the PCM will revert to a default shift mode, forcing full (unmodulated) line pressure and may inhibit the TCC function as a safety measure. This would result in the harsh shifting you describe. These circuits also connect to the PCM, so it may be beneficial to check the connections at the PCM for ALL of your problems.
The PCM on your vehicle should be located at the extreme right front corner of the vehicle, above and behind the RF wheel splash guard. It can be removed by sliding it downward from its mounting bracket. The electrical connectors can be removed and inspected for corrosion, damage, and moisture.
Once the problems are resolved, be certain that you drain the transmission, change the filter, and refill it with clean ATF. You'll want to get that shift/friction modifier OUT of the transmission as soon as possible.