The car overheats changed the thermostat still overheats put new waterpump &radiator still overheats & steams how do u reset computer?

Could I ask why you changed the waterpump in the first place?

Toyota are pretty bullet proof but if u are putting water in after 20 miles and there is defiantly no leaks it's got to be going somewhere and the only place is through the engine and out as steam and head gasket will cause overheating , over pressuring . Even if the oil is clean ( not creamy)

Did you change the thermostat? If not it may be the cause. You can check the thermostat by removing it and immersing it in hot water. If it is working it will open. The thermostat is usually located under the upper radiator hose.

If it where your water pump isthe vehicle would overheat. After you replaced the thermostat do you run the engine at idle with the radiator cap removed until the radiator fan came one? This will help push the air out of the system. There are two other possibilities. 1. The heater core is plugged. Back flushing the heater core may help remove the built up debris and get you heat again. 2. The blend door may not be fully transitioning from cold to hot. You should be ale to hear a district change in how the air sounds when switching from full hot to full cold. Let me know if you have any questions and I'll do my best to answer them. Thank you for using FixYa.com!

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Did you change the thermostat? And have you checked to make sure the fans come on? Is the temperature gauge giving you false readings?

when are you overheaing? highway or around town check electric fan operation radiator could be pluged when the waterpump and thermostat were done was the block bleed properly some cars have have a coolant bleeding proceedure

Smell for exhaust fumes in the radiator with cap off while it is running to check for a small head gasket seepage of compression. Also to narrow it down put a mirror in front of warm spark plug hole to check for steam escaping and fogging the mirror. I have seen water pump blades rotted off and radiators plugged with stop leak.

Change the radiator cap, it may be the wrong pressure rating which will cause the coolant to boil at a much lower temperature than designed.

If you are doing them all at the same time, do the water pump first. I like to do the toughest part first and then move on the the easier parts. Then the thermostat and then the radiator. Once you drain the radiator most of the engine coolant will come out making the waterpump easier to clean up. If you are doing them in different day's, alway's replace the waterpump and thermostat in pairs. If you can do the radiator at the same time, I would suggest that. Sometimes when thermostats get out of fluid, they sometimes will lock up and cause and overheat. Then you are replacing all the fluid and thermostat on a hot engine.

Only 2 parts remaining are the thermostat and waterpump. Always start with the thermostat when diagnosing an overheating problem. If the car is overheating constantly under all conditions and coolant is backing up into the reservoir, it's very likely to be the thermostat. If it only overheats at low speed or idling, it's more likely the waterpump.