Heater blowing warm air while idling
 

I have 2001 Cherokee Sport with 148,000 miles on it. The problem I’m having is the heater is blowing out warm air when I’m idling. When I press on the gas pedal the air gets hotter. For example, when my Cherokee is idling around 800 rpm’s it blows out warm air and if you press the gas to around 1200 rpm’s the air gets hotter & stays hooter until I let off the gas pedal. It seems as long as you’re pressing the gas pedal it blows out hot air.

When I’m driving it, everything seems fine. The temperature gauge is always between 210 and the line to the left. I just had the thermostat replaced.

Does anyone have any suggestions what might be causing this?

sounds like you either have low coolant circulation or a half clogged heater core. My suggestion would be to Run some prestone Flush through it several times. then put in new Antifreeze.

I'm not that familiar with the heater core, by flushing the coolant that flushes the heater core to?

just take your jeep to a radiator shop and tell them you want your radiator rebuilt, mine was doing the same thing but i took it there and they replaced the heater core and flushed out all the rust and it only costed me 100 bucks for everything

yes if you have the heat on full balst....cheapest thing to try

As long as I'm not idling the heater works great.

So the 1st thing to do is have the coolant flushed?

When they flush the coolant, can the tell if the heater core is going bad?

no, if you have a quick lube do it they will only be able to show you what came out. just make sure they actually "flush" it which mean draining the old coolant adding water and a cleaner and running it till it gets to normal temps (while running the heat) drain then refil with new coolant.

Have you checked the coolant level?

I believe the place I would have it flushed, does do that. I'll defiantly ask if they run a cleaner through it.

The coolant level looks good.

I have 40000 miles on this coolant and was planning on having if flushed before summer anyway, so now seems the right time to do it.

:cheers: He said hooter... he he he :naughty:

Or maybe just tell them that u think ur heater core is plugged.

After having my coolant flushed & the heater core backflushed, my heater is working great. I did have to get a new water pump due to it started to leak.

Thanks for all the advice.