2003 corolla lukewarm heat

[willy65000]

I've been having this problem with my corolla for the last couple of years. All vents on the right side of the car blow lukewarm. I've already purging the air from the system and that doesn't do the trick. Also, the car seems to be at the correct operating temp (middle of the gauge). Any ideas?

[dorman68]

I would check the 2 hoses (inlet & outlet)going to the firewall feeding the heater core. They both should be the same temperature, if one hose is hot and the other one is cold chances are you have a clogged heater core. If both hoses are hot I would check the temperature cable going to your heater controls and make sure everthing is operating properly, check for a binding or loose cable.

[ratko89]

maybe a slightly open thermostat

[dballard18]

I have a 2002 Corolla and had a plugged heater. The garden hose would blow through it, but the litle water pump would force very little through it. I went through it last weekend and fixed it by pulling the heater hoses and backfilling with a drain cleaner to chemically clean the heater. Worked wonders. The details are in my post in the 8th gen forum, dballard18.

[ryfly]

Clogged Heater core on the passenger. Be sure to find out first what clogged it before replacing or fixing.