PCars seems to act differently from Assetto Corsa when it comes to showing custom needles in the dials when in htm;l mode. They do not appear if the incoming Data is not there. Updated some code to get them to show.
PCars does push water and oil temp, oil pressure and even fuel pressure. Assetto corsa is slightly less complete in that area it seems. When you are using Assetto Corsa the temps are calculated and the fuel pressure is fuel amount instead.