Heater goes cold when decelerating, heats back up on acceleration.

[travsav]

Thought I was low on coolant, opened up the degas bottle, and the pressure sprayed some coolant out... The degas bottle is half full.

I don't have a monitor, but my temp sensor on my guage cluster is reading normal.

Sometimes on acceleration, and the heater warms back up, it has a lil burnt smell to it.

What do you guys think?

[travsav]

A friend of mine had the exact same problem with his '04 (mine is an '07)... He said his turned out to be a cracked head.

[dnf12908]

Mine does the same thing. I wonder if this is a fairly common condition on these trucks. On mine the heater output drops off going down a hill and comes on again going up. I, too would like to know if anyone has any insight into this.

[d and b installer]

not sure on the 6.0 but my town car did the same thing turned out to be a bad impeller on my water pump. the fins had "worn" down and would only move water under load.

[travsav]

Originally Posted by travsav

A friend of mine had the exact same problem with his '04 (mine is an '07)... He said his turned out to be a cracked head.

I kinda hope it's this, but probably not... My coolant level is great, the oil on my dipstick looks and smells fine, my temps seem fine...

I kinda think it's a partially clogged heater core, or my water pump... Only getting enough pressure during some load.

[travsav]

I removed the cap from the resevoir, and let it run for 30 minutes... shut it off, put the cap back on... This may have fixed the heat issue... not saying i don't have other problems, but my heat is always warm (still gets hotter when i accelerate, but i think this is normal)...