Finding coolant leak

2001 Tacoma 4x4 3.4 5 SPDR

I had coolant dripping from the drain hole right under the ac lines run into the firewall. I dont have any leaks into the cab. My first thought is heater core or is there some connection by the evap coil?

 

Coolant leaking from the evaporator box drain would indeed indicate a leaking heater core, unless it happens to be the inlet/outlet hoses on the firewall and just appears to be leaking from the drain.
I would take a towel and wipe everything dry, then start the engine and watch the area carefully with a good flashlight to pinpoint the source. Do you smell coolant coming from the vents inside the passenger compartment? (you will probably need to adjust the blend over to heat)

 

another option is to bypass the heater core connectors on the firewall for a few days and see if it goes away. Dont plug the heater coolant lines as they are integral to the cooling system.

Are you sure that it is coolant and not the evaporator drain just doing what it is supposed to do?

 

How much coolant have you had to add??

Pressure tester is your friend.

Your sure it is not rust colored condensation ??

Hot humid days it just pours out of my truck

 

Water pours out of the drain hole on mine when I run the AC. The AC evaporator is pulling all of the humidity out of the air where it goes out of the drain.

 

If the above suggestions don't work you can get a bottle of UV dye and a UV flashlight from Amazon for less than $20

 

Go down to Vato Zone and rent the coolant pressurization kit, that way you can check the whole system cold and not get burnt,, you can check your radiator cap also,, which most people overlook.

 

Well I pulled the ac core out and no corrosion or leaks. The liquid I was seeing was all from the evap. After pulling the fan shroud I spotted the leak from my radiator tank. Lots of wasted time.