97 Wrangler Heat Not Working

Hi All,

This may be kind of a boring question for you guys, but hopefully you can help:

My girlfriend has a 97 Wrangler with the 4.0 engine and 5speed. The interior heat doesn’t work too well, only really gets luke warm at best. She says it used to really work great

*The temp guage goes right up to the middle and stays after 10 minutes or so, that looks normal

*The heater hoses seem to both get pretty warm and fairly equally, but not so hot that I can’t hold my hand on them. Didn’t really know to squeeze them to see if they’re flowing well,and I don’t have the truck now.

*Not sure if the radiator hoses are flowing when the truck is still cold, didn’t really know to check that either.

*The blower fan works fine at all speeds

*The defront, footwell, chest level vents all work and can be selected.

*The air doesn’t seem to blow super cold, when it’s put all the way to cold. Even when it’s cold outside. There is some change in the air temp though.

*The coolant definitely looks pretty dirty, but not totally gross. The level in the recovery tank looks ok.

Any ideas

Any help would be appreciated

Since the coolant looks bad, I would change it. Carefully remove the hoses to the heater core. Cut them off and replace them if possible so you avoid at all costs twisting the connections. Flush the heater core separately with a garden hose. Use the coolant recommended for your vehicle even if you can 't find it at the closest parts store.

Not many respond to Jeep questions on this forum. I have a Cherokee, 92, at about 100k, I tried a complete flush because it was running a little to warm by the gage. Ended up replacing the radiater, thermostat & of coarse another flush. Not saying you need a new radiater but Jeeps have a rather small aluminum radiater. You should really consider a complete flush. Don’t know your location but summer temps tell alot on Jeeps systems. Cold weather tells if it is not circulating properly. Hope this helps.

If your coolant looks dirty, you may very well have a partially plugged heater core. When the engine is hot, feel both of the heater hoses. They should be very close to the same temperature if water is circulating. Note that the host from the water pump is the supply. If the other hose is not just about as hot as the supply, follow Beadsandbeads’ instructions for flushing the core. Then flush the engine and radiator. I usually remove the bottom radiator host for this. Also, check to see that your blend-air door, on the passenger side, is operating properly. Move the temperature control and watch the door operation. You may need to adjust the cable. This cooling system is supposed to automatically bleed the air. Good luck!

I think your problem is the air temp blend door, as KLRTom suggested. You said the heater core hoses are hot, so the core is hot, and you said it doesn’t blow either hot or cold air, only luke warm. The blend door is not moving. Find out why and fix it.

Of course, all the other recommendations about replacing the old, dirty coolant are valid, but they won’t necessarily make hot air come out of the vents. When you replace the coolant, replace the thermostat, too.