[andrex03]

Well it all started last year during winter my car started to over heat, i replaced water pump and valve. It stopped over heating but the only problem was that the sensor would bring temperate up to 120 and then it would go down or eve stay down if i left A/C On. But 4 days ago it started to over heat again until red and A/C couldn't even drop the temperate at all, so i had replaced temp sensor and a piece which is like a "T" that was clogged as my mechanic told me. But after i pick up the car after 20m driving started to over heat now they are saying could be the headgasket, what should i do? (the fans work also)

Thanks for any help!

 

[maximuz]

Theromostat stuck closed, waterpump could be faulty. Temp sensor/gauge shorted. Start the car make sure there is coolant returning to the resivoir while idles at 2000-2500 rpm. If it does nothings clogged. Does the engine feel excessivly hot? Getting white smoke from exhaust? So me just sounds like the thermostat

 

[Shameless]

I would start with a different mechanic since it doesn't sound like they diagnosed anything at all, they just figured you would throw money at them till the problem went away.

It could have been as simple as bad coolant, it can be tested. Your thermostat can be tested by a simple diagnosis without ever removing a part from the car. You can check for head gasket problems by using a dye that will change color when exhaust gases touch it, putting it into the coolant.

Cooling parts rarely clog, other than radiators(rare) and the heater core.
Even with a head gasket, mixing wrong coolants, etc... It's very unlikely pipes will clog.

If a single shop did all this work to no avail I would demand a proper diagnoses for free since I'm sure you've spent a ton of money, for what seems to be no gain.
Either that or go to another place entirely.