I have a 1996 Jetta VW [Trex] 2.0 I replaced the water pump and thermostat. It is still overheating. The top hoses are all real hot. The bottom hose and the radiator are cold. There is no water in the radiator. I've been told that it is probably an air block. What should I do? Thanks
Jack up the front of the car and put on jack stands and chock the rear wheels. Or you can use ramps.
With the vehicle on an angle, the trapped air will now be able to escape. On some cars the radiator is a different height than the engine and the air gets trapped.
With the engine cool, remove the radiator cap. Start the engine let it get hot.
Watch the coolant level and fill as needed. When all the air is dissipated the engine will return to its normal temperature.
It may take awhile or even another try, eventually all the air will escape.
Be sure the thermostat is installed properly. Recheck your work.