94 ranger heater n temp gauge

Hi i have a 94 ranger 2 wd 4 cyl the prob I'm having is i get very little heat when driving when left to idle air gets nice n warm and also the temp gauge only works wen the key is off wen driving the gauge might move alittle but it's so little I'm not sure it does but as soon as the key turns off it rises to operation temp so far I've flushed radiator and heater core put new water pump, thermostat and new temp sensor any help would b appreciated

Thx

I just was out messing w ranger again only way i could get heater working close to right was put cardboard in from of rad n it was almost 70 here today if any 1 nos wats going on w it i could use the help i dout it will b that warm wem it starts getting cold thx

Welcome slp4days. I would take out the thermostat and look to see if it is stuck open. Do this when the engine is cold (hasn't been run) so you don't get burned by hot water. Are you sure you have the correct temperature thermostat? If it is closed then put it in a pan of water and begin to heat the water on your stove. Buy a cheap thermometer that will go at least 212°F and put it into the water as you begin to heat it. Watch the thermostat and when it opens look at the temperature. It should read very close to what the thermostat is supposed to open at.