when my truck is idle i get cool air, but when i rev it up to 2000 rpg i get hot air. Does this mean i have a water pump thats worn out?

 

also, how hard is it to change the water pump?

 

that just sounds weird, what is your engine temp doing...? That would be what i would guess...ne body else have any ideas???

 

sounds like some typr of blockage. have you flushed the heater core at all? if not find out which is the inlet and outlet. using the outlet hose flush it with the garden hose in reverse this will flush out anything that is clogged. and not force it farther into the core. also if your pump is bad truck would over heat. also you might have a bad thermostat. before driving take a piece of cardboard and place it in frt of radiator and drive it around for awhile keep an eye on temp so it doent overheat. if this helps try changing the stat.

 

I have flushed the entire system forwards and backwards. I've never had overheating problems. Engine temp has always been in the norm. At idle its just warm air, but around 2K or higher i get hot air. thermostat has been changed.

 

very strange let me know what you find...now that you have done this

 

That's the heater core plugging up. I have never heard otherwise with this problem and it is extremely common here's the link to a write up. https://dodgeforum.com/m_640588/tm.htm

 

I flushed the entire system. I doubt that its pluggin up again.

 

you could have an air pocket in there... try bleeding the air out of the system again...

 

ive done that twice. Thats why i thought the pump could be warn out, but not broken. Because like i said if i hold the revs around 2-3k i get hot air, but as soon as it idles i get warm air. Think it could be that?