Make sure that the lower radiator hose gets hot. Don't assume the pump is OK, All your symptoms point to a bad pump.
Check the radiator core for even heat across the core surface (use a heat gun or use your fingers by reaching through the
fan fins ***be careful***.
I can not diagnose over the internet, I can only tell you what I know from experience. Have a shop look at it for an accurate diagnosis.
Thursday, October 10th, 2013 AT 6:02 PM