Hey guys how's it going? I've read through 6 pages of previous posts on this problem and haven't really found exactly what I'm experiencing so I wanted to ask.

My heater sometimes (not always) will blow cold air regardless of RPM's until I stop the truck and shut the motor off and then start it again and then the heater works just fine...

I can't imagine this is a blockage and I know it's not low on coolant.

Any thoughts?

 

I would inspect the heater hoses first. If one is hot and one not, the heater core could be blocked. If both are luke warm, the t-stat is bad. If both are hot, the actuator is not moving to direct the airflow through the heater core.

 

Good idea I'll try that, thanks! The thing that gets me though is that shutting the truck down and restarting fixes the problem...???

 

Let me piggy-back on HouTeX's suggestion; check for the possible hot and cold hoses, before, you sw off the engine. Switch off engine. Wait as you've done, then restart the engine, let run for a minute or 2, re-ck the hose temp for any change on the 'was' cold hose. If there was a change to the cold hose, the question is, whats happening? Would this be what I've heard of as 'upper hose air-locking' ?

 

Yeah I'll definitely try that then next time it decides to do that... thanks!!

 

let me know if you find out the problem, i had the same issue with my heater. But now my heater is just stuck on cold.

 

Actually now it's not doing it anymore and it's just always cold on the driver's side but warm on the passenger side so I'm pretty sure it has to do with the blending door but I'm trying to find more threads about it and how to fix it.

I think I might have to tear the dash appart which sucks because it's starting to drop below zero here in Colorado now...

 

anyone else have this problem and it seems as if the truck doesn't get that hot the thermostat gauge will only go up to a little before half way

 

Hey so I found this after searching some threads which helps a TON!! It's probably going to save me thousands. I'm almost positive it's my blend door so I'm going to dig into it. Thank god for the "how-to" video generation huh?

http://heatertreater.net/Dodge%20Ram%20Video.html

 

thanks! the only thing is none of the vents blow warm or hot air and i checked my heater lines and am thinking that i'm going to have to flush my heater core. i'm going to do some more research, but i will also keep you posted. thanks for the tips!