PumpinIron

The vehicle in question is a 2000 Jeep Cherokee with 25k miles on a completely remanufactured motor.

The problem I am having is that now that it's getting to be colder weather outside I am starting to use the heater. I noticed that the heater doesn't seem to blow all that warm. The vehicle always heats up to operating temperature and the gauge sits where it's supposed to right in the middle. However, even when I turn the heat on full blast and the warmest setting it's just warm, not hot.

Instinctively I'd think it would have something to do with the heater core, but if the heater core was blown I would think that there would be no heat at all, period. The other odd thing is that the faster you go (i.e. highway speeds) the warmer the air will get.

Still, for having the temperature set to the warmest setting and the fan on max, it definitely isn't blowing as hot as previous cars I've had before. Unfortunately this is my first Jeep so I have nothing else to compare it too.

Any ideas?

GAPANDA

Mine had a similar problem. Once it got cooler it didn't seem to get warm like it did.

Had another issue and pulled the lower radiator hose and had to refill. This seem to make it worse. Thought maybe I had a air bubble. Attempted the Jeep 6 cyl burp. Didn't make enough of a difference.

Bought a thermostat at the dealer. $20.00 and that was after a pricing negotiations, their original price was $26.00. Had previously read too many posts about multiple after market failures. Factory unit came with gasket for the housing.

Found out.... NO thermostat was installed.

Can't tell you the std maintenance issues I'm dealing/have dealt with thanks to the PO of this Jeep.

During the replacement refill process and made sure to flush ONLY the heater core as well, in both directions.

NOW, I have real Jeep heat once again.

Good Luck.

MUNCIE

Mine only would get luke warm at best. I flushed only the heater core, both ways. It got a bit warmer so I flushed it again and now its comfortable. What does your coolant look like?

elevol92

Flush your heater core and check the heater control valve. My 88 was doing the same thing, I didn't look into it because it was still hot out, before the cold came the valve broke and I looked at the valve and it was filled with gunk from years of coolant. I replaced it and she's blowing enough heat to cook a thanksgiving turkey

PumpinIron

The previous owner is the person who installed the remanufactured motor. He gave me all the documentation and receipts for it. He also installed a brand new radiator in the Jeep as well so I know that part is good.

I'll try flushing the heater core a few times and see what that does. Where is the heater control valve located on this thing? I have yet to pick up a manual...

Unknown XJ

You don't have one.

PumpinIron

So then I assume you mean the 97-01 XJ doesn't have one?

Guess I can try and flush the heater core then.

Jeffvador

Did you get your heat going?

dogkatcher

i just replaced a brand new heater valve .. '93 xj .. after $363 for a new rad, coolant flush, core flush .. rad / core clogged .. explains the malfunction of heat valve .. too much pressure or bad brown core water

clogged heater core & rad ,, wasnt good

im leaving heat on at all times .. to circulate the core

plan on a re-flush depending on coolant color .. we'll see

also watching windshield for dis-color .. looks good so far

cruiser54

Aside from the fact that the heater control valves break unexpectedly, the fact that they clog and allow the coolant in the core to stagnate throughout the summer months is further evidence to remove and eliminate those pesky critters. Way cheaper, too.

PumpinIron

Haven't got it fixed yet. I need to find some time to flush the heater core because my temp gauge sits at 210 just fine without any issues.

So no one ever have me a for sure answer, does the 97-01 XJ not have a heater control valve?

Unknown XJ

Yes sir you are correct....... My 98's heat wasn't all that when I first got her.
I ended up cleaning my system and changing my coolant. But I didn't flush the core or the system as a whole. My e-fan was dead so I replaced it with one from a 99 and I also replaced my fan shroud. (Seemed To help.)
But now my AC clutch intermittently engages (unlike it's usual cycles while on defrost) there seems to be some bearing drag present as well.
So it seems I have a different issue with my heat lol. How's your e-fan doing? How's your fan shoud looking? Thing's also to consider.....

Turbo X_J

No heater control valve.

First thing to check:
Are both hoses going to the heater core hot when the engine is warmed up?
You could possibly have a blend door issue if the heater core is getting hot coolant.