2005 sti stage 3 with new water pump. have mishimoto racing radiator
Overheating, Only when air conditioning is on.
fans are coming on correctly.
coolant; overflow was empty, upper radiator was full
filled overflow, ran it for 10 minutes with heater on, and it took up half the over flow. still running warm to next line up, not in the red
so next filled overflow again and ran it for 25 minutes with radiatior cap off, and heater on.
didn't take up anymore, didn't see level drop any.
overheating is taking place with easy driving, highway or local doesn't matter, but having the air conditioner on does.
when it overheats it just goes up to the next line, never into the red
when it does if i turn off the air, it cools right back to normal.
could the compressor pull enough to make the water pump belt not turn the water pump correctly.
i have a thermastat and am ready to change it but i can't see how that be the problem???