00maroonXJ

Hello, I have a 2000 Jeep Cherokee with about 135K on it. It runs great and is easy to fix when things go wrong. The ONE thing I can't seem to fix is the heater. I haven't done a heater core, but short of that, is there anything else that is known as a common problem before I forge ahead and tear apart my dash to fix this. I'd really like to get it fixed before next snowboarding season, so while the weather is nice, I want to get it permanently fixed! Please keep in mind that I already changed the radiator. It DID seem like I had a little heat right after doing that, but now I got nothing..........So with all that being said, ANY suggestions would be highly appreciated. Thanks!!!

alsxj

Well, few things first turn the heater on with the jeep running, feel both hoses on the heater core, the inlet is hot and the outlet is cold then your heater core is blocked. You can try back flushing it but back flushing may result in a leaky heater core. Also I'm not sure if the newer xjs have them but check the heater control valve as well. Another simple thing but I'm sure you checked but it isnt low on coolant?

alsxj

also is it getting up to operating temperature? If its running cool you could have a stuck thermostat.

00maroonXJ

Thanks for the reply! No I'm FOR SURE fine on coolant. Previous to this I had a leaky radiator and was chasing my tail to find the leak because it still was leaking after a brand new radiator. Then I replaced my t-stat because it had a leaky seal on the housing, so I know my t-stat is good, and I know the fluid level is perfect. It also gets to full operating temp just fine.... After all that I also figured out that I had a leaking water pump gasket, but some alluminol did the trick on that.

alsxj

No worries man, glad to help and I know it seems like a silly question on the coolant level but got to ask. Anyways I don't think your xj has an heater control valve so nevermind about that. Did you check those lines for temperature? With the jeep running at temperature and heater full blast on. And did you install the right temp stat?

CharlesS

Might want to check the mix box to ensure the damper is closing off the cool air and opening the hot air.... Could be a vacuum problem since the climate controls are vacuum actuated....