90 325is, pressurized heater control valve

[dakarm34]

I've been trying to track down why the coolant temp goes up from half way to 3/4 and sometimes slightly higher. I flushed the system tonight, and noticed the inlet hose to the heater core was rock hard, hot as hell and the outlet hose was not. I disconnected the heater control valve and it seems to have fixed the problem. I still have to take the valve out and test it. The heater core doesn't seem to be leaking, however there is a very slight amount of coolant near the h.c. valve, probably the 0 rings need replacing, especially after all of that pressure from the valve.

How do it know it's the valve and not the console's temperature control rheostat? I understand that it will vary the voltage from 6-12v depending on what the occupant desires. She said this winter that she didn't have much heat in the car. Perhaps it's the rheostat.

The car has 200k miles on it and has been well maintained. I've replaced the radiator cap, thermostat, fan clutch, all hoses - they were shot anyway, flushed the system. A T.B. was done about 10k ago, so the water pump is new, she wrecked it about a year ago so the radiator is new.

[BMWCowboy]

Not sure about ur temp problem>>may be a guage problem or cluster>>as long as its not overheating....may want to check water-pump....some places replaced plastic water-pumps with the same plastic pump Also on this car the heater cable clip comes loose & you can move the knob but the cable doesnt move >>pull out the radio and trace the cable....its a yellow clip on the rt side of console