Hello! I have a 2003 Jaguar X-Type 3.0. I'm having a problem with the heater. It blows warm air but not nearly as warm as it should be. The coolant level is fine. The temperature gauge is reading normal. My girlfriend has the same model car. On my car the measured air temperature at the front facing vents is 104 degrees. On my girlfriends car it's 138 degrees. Both cars in high heat mode. The radiator hoses and heater hoses on my car read about 10 degrees hotter than on my girlfriends car. I checked the coolant temperature on both cars with a scanner and they're both at 190. On my car I can squeeze off the upper radiator hose with my hand. I can't do that on my girlfriends car. I'm wondering if the water pump is worn and not producing enough pressure.

I'm pretty much down to 3 things.
The water pump.
The thermostat.
The blend actuator and blend door.

Any advice would be appreciated. Thanks.

 

Based on your post I'm thinking you've got some clogging of the heater core. There's YouTube videos to help. Here's one:

 

Bzeigler, it is possible that the water pump is not outputting enough. But, this is normally associated with a car that overheats too. Like what Swingwing said, odds are, you are looking at a clogged heater core. I have found that the easiest thing to do is to simply drain the coolant, remove the hoses going to the heater core, then blow some air through the hoses and through the heater core. If you use your mouth (make sure the end of the hoses are free of coolant), you should be able to blow through the heater core with no real feeling of restriction. You can also use an air compressor and give it quick bursts of air. This will tend to "hammer" any clog loose and blow it out. For really stubborn things, add a little water to act as a water hammer. When the clog clears, you will know because when you give the burst of air, it will come out the other side with some vengence.

If you need more info on doing this, let me know.

 

flush it all out and start again

 

Bzeigler: Your recirculation blend door may be stuck open, allowing the blower to constantly suck frigid Minnesota air into the cabin. It's easy to check.

You say: "On my car the measured air temperature at the front facing vents is 104 degrees. On my girlfriends car it's 138 degrees. Both cars in high heat mode."

I assume both cars have air recirculation "on" which should close the recirculation blend door to keep cold air out. To see if it's working properly, switch the air recirculation to "off" and the air temperature from the vents should drop significantly (on a cold day in Minnesota). If the air vent temperature drops in your girl friend's car, but not in your car, it's probably because your recirculation blend door is stuck open, allowing cold air in all the time.

Here's a few threads on this topic, because it's a common problem - more common that a clogged heater core in our X-Types.

https://www.jaguarforums.com/forum/x...indows-135809/

https://www.jaguarforums.com/forum/x...indows-110519/

https://www.jaguarforums.com/forum/x...rculate-63354/

https://www.jaguarforums.com/forum/x...89/#post579583

If the heater core is clogged, it's probably because someone mixed two incompatible types of antifreeze without first flushing the coolant. The prior posts address that problem & solution.

Let us know what you find - it helps the next person with this problem.