99 xj heat problems or cooling flow ?

I have a 99 xj . Had head gasket replaced last March along with water pump. Jeep runs great but when it started to get colder there was no heat just warm at best . Just getting around to looking at it now. Flushed and back flushed heater core good flow both ways. T-stat new, top heater hose hot hot bottom not as hot . Temp is right at 210 no overheating . If I take the top heater hose of from t-stat no flow, if I take bottom hose of water pump it spits a little coolant , but not a steady stream or anything . When I flush the whole system from top heater hose it feeds all the way back out radiator . So I'm thinking no blocks. Blend door works , can hear door closing when turning hot to cold. My question is could it be the water pump ?

I have the same year and i just cut a hole in my heater box to feel if the heater core was getting hot. It was not, but my top and bottom hoses to heater core where hot. i havent fixed it yet but im going to try to flush just the heater core.

The flow is from the T-Stat housing to the heater core and return to the pump. I would disconnect the hoses from the T-Stat housing and the water pump and blow either air or better still, water through them to check the heater core for blockage. Both hoses should be hot if you are not running the heater in any way.

How do you check the blend door? I just had replaced my condenser and refilled with refrigerant and no A/C at all.

Heat works great but the A/C just blows warm air.

Suggestions?

2001JeepXJNS said:

How do you check the blend door? I just had replaced my condenser and refilled with refrigerant and no A/C at all.

Heat works great but the A/C just blows warm air.

Suggestions?

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just on the passenger side of the tranny tunnel is a knob sticking out of the bottom of air ducts. turn your temp from hot to cold and you should be able see the knob turn.


im on my 3rd water pump on my 99 xj. they are notorious for turning anti freeze acidic

Flushed and back flushed the heater core separately . Looks like time to try the water pump. Thanks All

Finally got around to changing the water pump . Pulled it off and saw the impeller was eroded away . It looked like a fan blade . Now its running right at temp and the heat is hot again .