Bad heater in a 2000 Silverado

[the_marquis78]

Well Charlie, you asked for it. I've got a 2000 Silverado 2500 and the heater blows cold air. What could be possible causes and/or fixes and could someone who's only somewhat mechanically savvy pull it off? What do you think? Any way of figuring out what the problem is w/out paying someone too much to do it?

[bigtreepu]

possibly the heater core. Is there any smells coming from the heater?

[4BangR-X]

First place to check is your coolant level. Also, Id look and see if there is any dampness(coolant) on your passenger side floorboard.

[Mav]

actuator? haha, I just see those things going out everyday... had to throw it in the mix.

[GRRRR8]

Make sure coolant is full and engine is warmed up. Then grab each heater hose. If both are hot its a actuator/dash problem, if both hoses are not hot then the heater core is plugged up or low on coolant.

[the_marquis78]

Make sure coolant is full and engine is warmed up. Then grab each heater hose. If both are hot its a actuator/dash problem, if both hoses are not hot then the heater core is plugged up or low on coolant.

Again I apologize for not knowing that much: what coolant are you referring to? Is there a separate coolant for heater?

http://i85.photobucket.com/albums/k46/the_marquis78/hoses1.jpg

http://i85.photobucket.com/albums/k46/the_marquis78/hoses.jpg

Are these the heater hoses? One was warm and one was not. The one on top/closer to the center of the truck was the warm one. Thanks for the help!

[-Ray-]

Those are the heater hoses. One is the supply line, the other is the return line. Two things can be happening IMO. Either the heater core is blocked so water isn't passing through it, or the part that directs water through the heater core is closed off and not opening.

[GRRRR8]

Make sure the system is full. That is the most common issue with loss of heat. The LS truck engines are known for water pump gaskets seepage. So if it is low this would be the area to look in.

[-Ray-]

...and what Charlie said. :)

[wreckwriter]

Again I apologize for not knowing that much: what coolant are you referring to? Is there a separate coolant for heater?


No, it uses the coolant in your radiator.

[todds87ss]

switch from hot to cold and listen carefully for an airflow change. No change, probably the actuator.

[the_marquis78]

Yeah i figured the coolant was all the same. I filled up the coolant and it made the air just a little warmer but still mostly cold. I didn't hear that airflow change so if you're right, the actuator may be at fault. I'm probably just going to have to take it in to get looked at.

[-Ray-]

How low was the coolant? Is the engine reaching operating temp?
I've got basically the same truck, and it has the heater from hell. I'm willing to go out there and see if there are any moving parts.