Change engine coolant on a 2002 Corolla

heat should be set to full hotness. there should be a engine drain also a radiator if you can get to both that would be good in flusing. toyota long life(red) or short life (light pink) is the best to go for any car. for bleeding i personaly just fill the radiator and try to squeese out what ever air i can from the hoses. then i start the engine off with the radiator cap off and keep filling it till it stops going down after a short while.

If its really dirty and you want a good flush, follow this.
Drain the coolant as instructed. Plug the drain again, remove top hose. Remove thermostat, put neck back on without thermostat. Reconnect low hose if you had to remove it to get thermostat out. Put garden hose into rad from top hose openning. Leave rad cap off. Turn on the garden hose so water keep going into rad. Make sure hose stay in rad, start the car with heater on. Keep idling until clear water come out from top hose openning on engine side.
Follow flush instruction shown on flush bottle. With thermostat out, top hose reconnected. Make sure you idle the car till water get hot. Rev it a bit to help heat up faster.
Make sure you put thermostat back after you finish

Thanks. Does anyone know where the engine drain plug is on a 1.8L DOHC (1ZZ-FE) MFI?????? Radiator plug I can see on the bottom of the radiator.

OK. Thanks. But how do you open it? Is it a tap that you turn clockwise to open and drain?

I cant make out what that plastic purple thing is?

My apologies. The "plastic purple thing" is actually the engine drain plug, which is metal, it's just really rusty (the car is now 12 years old...) and the purple hue is because I'm using an LED flashlight and the white balance of the photo is off.

It was actually a bolt, I BELIEVE a 10 mm (or maybe 12?). I attached a plastic hose (I used the same as for the radiator plug, it's close in diameter) and used a 10 (or 12?) mm socket wrench to open the plug (lefty loosy). I didn't have to completely remove the bolt; just loosened it enough to see coolant running out. Of course, you can only turn the plug about one ratchet click at a time because it's in such a tight location. And quite a bit came out! It's definitely worth draining if you can find it.

Hope this helps.