Hey guys, so i recently did a heater core replacement (a pain in the and now the heater doesn't want to work at operating temperatures. The coolant levels are fine and i already bled out the system. I also hear a popping sound after the car is off but I'm pretty sure that, that is the thermostat.... so it must be working. All of the hoses are hot going and leaving the heater core. The engine room is pretty hot too if that has to do with anything. Although there is one thing, the heater control valve doesn't seem to move when i turn the heater dial. On the heater control valve there is an arrow pointing one direction so i turned it all the way manually and the heat still doesn't seem to be working. Getting Pretty desperate as the temperature start dropping. Just wanted to hear your guys two cents. Thanks for reading and commenting!

Honda
Accord
1997
V6
EX
Auto

 

If you're getting no heat w/ heater core valve open, then blend door is likely not responding to command for heat. Not plugged in or defective blend door motor seems likely.

Was system checked and working after heater core replacement?

Is this ATC or manual controls?

good luck

 

i believe your talking about the inside vents? i'm not quite sure. but i took the out side part of the gears on the side of the heater unit to manually open and close the vents but still didn't work. and i'm sure its ATC.

 

There is a stepper motor that drives the blend door for ATC controls. If it stays in cold position none of the air is forced over the heater core and no heating can occur. Need to trouble shoot this system; check motor and linkage.

You will need a shop manual to drive your diagnostics. Most Honda ATC systems have some self-diagnostic systems that generate a code when prompted correctly from controls. I don't believe I've seen a download for the 97 V6 Accord, but check Online Manuals post in DIY forum for possible downloads. Next option is to check ebay for a used/new manual, and finally helminc.com may have a new manual.

good luck