Ok during the summer i had a leak from heater control valve so i replaced it today i had my heat on it seemed to be working ok but i have one of those test probe thermometers which go in the vent the heat was coming out about 120 degrees my question is should it be hotter? I thought i remember it coming out hotter last winter. I have another car i tested the heat temperature out of the vents and in that car it was coming out about 160 degrees? ANy input?

What was the temp outside? was it checked with the fan on max?

Outside temp was maybe 50 degrees and fan was on max any thoughts?

It is possible you have air trapped in the heater core from replacing the valve. Running in park with the cap off will help burp out the air. Rev up the idle every once and a while to help push out the air. See what the temp is at highway speeds. If it still hangs around that temp or gets hotter than I would be concerned with possible the heater core starting to plug up or the air pockets finally moved out. If it gets cooler I would be thinking the t-stat isn't functioning correctly. 120 isn't bad but I would be a little more comfortable with around 140 out of the vents. Which could happen with the fan one notch below max.