Thread: QR25 cooling: no tech sec?

obviously this isnt SR20 related, but i need help. its winter in NH and my moms heat is acting up in her '03 altima (QR25 motor). whether in park, neutral, drive, or reverse, the heat is ONLY hot when on the throttle! ideas? i did the therm, H2o control valve (2nd therm), and flushed the coolant. im thinking there is a clog somewhere in the system restricting the flow without high revs on the motor and the water pump forcing coolant passed the clog. when not on the throttle, the air slowly cools off getting cold. im thinking, with a restriction, the coolant is just sitting in the heater core and the blower motor is acting like a ratiator fan cooling the coolant trapped in the core eventually blowing cold air. that or the core is just crappin out. the passenger side floor is dry though. i didnt have a hose avail with the winter and freezing, so the system wasnt actually flushed, just swapped. any and all ideas are welcomed!!! i DO NOT want my mom at a shop or without heat! thanx!

also...the car is not overheating, no air in the system that i can tell, and the therms are functioning. i boiled them before install. is there a bleeder like on the SR20 for the coolant system? im thinknig maybe somehow the system got airbound. on this motor, the therm is on the lower radiator hose, and the water control valve is on the upper hose. the therm is 180* and the WCV is 206*. the lower hose oddly doesnt get hot. im lost! the therm is motor side, the WCV is radiator side.

well, apparently today, the problem is gone. she called me and told me her heat is working 100% in park, at stop lights, and in motion. i think it was a clog in the system that broke free. if only it werent freezing temps here in NH i would have flushed the system good with a garden hose! the hose is long put away for winter though. oh well. 2 new therms and 1.5 gallons of new coolant did the trick....for now.