finally!! found the problem! water pump had absolutely no fins left on the impeller, amazing it was even circulating at all. pics coming soon
you wont believe how bad the pump was. these are some valuable points i learned throughout this experience so ill share them here
Removing the guts out of the thermostat was a good method for eliminating thermostat as a problem, so i will put a new one in soon.
Temp sensors serve 2 purposes.....
1) tells the thermo fans when to engage ( and if your fans engage at half temp then your sensor is doing its job )
2) Tells the computer how hot the engine is operating at and controls fuel to air mixture ( if the car runs too cold the sensor will tell the ecu to run a bit richer - like a choke)
Jacking up the front of the car to put in the coolant is a great idea also (had a 4l air pocket as well) and ensure proper bleeding of air from the cooling system at operating temperature.
flush the radiator to test if it has any blockages...the radiator should not be able to fill up if it is not connected to the car. and the flow out of the radiator needs to be the same as the flow going in . block the bottom hose off first and fill it up then release the bottom. if you have a good flow your radiator is fine
Thermos can either suck or blow....make sure it is sucking air through the radiator and not blowing through
if everything above is fine and your still having troubles after replacing most of these components then it is more than likely that your head gasket is blown. a test on the water will confirm if this is a problem and most mechanics perform this test for around the $40 mark