My 2002 X-Type heater only blows cold air unless I do 60 mph or more. Any ideas what the problem could be?

 

Jeramia: Welcome to the Jaguar Forum. You'll find this to be a place where Jaguar owners enjoy sharing their wealth of knowledge, tips and tricks about our X-Types.

The dodgy heater may be trying to tell you the coolant level is low. Pop the hood and check the coolant level in the reservoir over the left-side front tire, the driver-side on US cars.

If it's low, this thread describes how to refill it, 'burp' air from the system, and check the typical locations for coolant leaks.

https://www.jaguarforums.com/forum/x...-stays-129940/

If your X-Type has a coolant leak, don't neglect this. Running the engine with low coolant can overheat and seriously damage it. Keep a jug of water in the car and closely monitor the coolant level until you find and fix the leak.

Keep us posted on what you find, and if you'd like advice on how other's have fixed similar issues.

 

The coolant is full, no leaks. But I have had the car 6 years and never changed coolant, should I empty it and renew? If so what antifreeze is recommended and how much?

 

Jeramia: If the coolant level is ok, I would not mess with it. The reason your heater blows only hot air could be:
1) a blockage that prevents coolant flow to the heater core, or
2) a stuck door in the air handler under the dash / behind the radio such that air flow is bypassing the heater core.

This thread describes how to check and fix either issue:
https://www.jaguarforums.com/forum/x...heater-128810/

 

Thanx DW. If it was either of those things would it still blow hot at 60 mph but not at idle?

 

Jeramia, the problem that you talk out could possibly be a blockage in the heater core. I guess the question is whether it is blowing hot/hot air or if it is just warm air. If it is hot/hot air, then a blockage is not very likely. if it is only warm air, then the blockage would be the more likely thing.

Odds are, what you are seeing is more something along the lines of a water pump that is starting to go and it is not able to make sufficient flow until the RPMs are up and then develop enough pressure to push the engine coolant through the heater core.

Something that you can try is going out on the highway and cruising for way 10 miles at 70 mph (get things up to temp and stable). Then immediately get off the highway and find a spot to park (can even pull of to the side of the offramp, big thing is to get the engine to idle as quickly as possible). Watch the temp gauge and see if it rises. If it does, then odds are you are looking at a bad water pump.

 

OK thanks dw. Will try that tomorrow and let you know the results. Thanks again for your time and help.

 

Jeramia: That last response re: a weak water pump was from Thermo, who is far more an expert than I.

In addition to a weak water pump, another possibility is a partial blockage in the heater core. This doesn't happen often, but can occur when green antifreeze (ethylene glycol) was mixed with orange antifreeze (Dexcool). The blend can form a gel.

To check for a partial blockage in your heater core, take a look at the hoses running to and from the heater core. Here's a picture, courtesy of PanamaJag, who, by the way, cleared a clog from his heater core in this thread:

https://www.jaguarforums.com/forum/x...s-cold-127794/



The line labeled HOT and close to the battery supplies the heater core. The line labeled COLD is the return from the heater core. Warm up the engine, keep it running, set the temperature in the passenger compartment to LO, and turn off blower. Carefully touch the hoses to & from the heater core. If both are hot and about the same temperature, then coolant is flowing through the heater core. If the return line is noticeably cooler then the supply line, then little to no coolant is flowing thru these lines, either due to a weak water pump or a plugged heater core.

PanamaJag disconnected these hoses and flushed a ~pound of junk out of his heater using a water hose. See the end of his thread for details.

 

Jeramia, if you had the car for 6 years and never changed the coolant you probably should. It is long overdue to have that done. That will not fix your current problem, but something that should be done as part of regular maintenance. Plus, you do not know how long before you bought it since/if the previous owner ever changed the coolant. You should do that every year or two. At the very least have it tested. Might save you some trouble down the road.

 

Jeramia, something that you may want to consider if if you have an air compressor, drain the coolant from the engine (probably a good idea at this point) and then disconnect the hoses going to/from the heater core. From there, you can take the cold line and apply some pressure to the hose and blow out anything that may be in the heater core. The heater core will easily take 60-80 psi of air. If it blows freely, then you can almost garantee that your problem is the water pump. If you are getting very little air, then you are looking at a clogged heater core.

If you are thinking blocked/clogged heater core, I would recommend first using a "water hammer" to attempt to clear the blockage. Before you flip out and wonder what a water hammer is, all you are doing is shooting a small slug of water down to the heater core and using the speed of the water to hit the blockage and dislodge it. To do this, you simply pour a little bit of water into the hose and then hit the hose with compressed air. This will shoot the water down the hose and into the blockage. If you get too much water in there, you can simply blow it all the way through or just blow it backwards. You will know when the blockage clears as it will come shooting out at you. So, be ready for that. May want to have the return hose pointed somewhere away from you.

 

Thankyou everybody. What a brilliant forum this is.. Wish I'd found it years ago! I got the engine up to normal temp and checked the heater hoses and, sure enough, the return is cold, so am now attempting to clear with the garden hose. Which antifreeze is best for my car? 2002 V6 2000? And how much?

 

Jeramia, when it comes to coolant, any of the major brands are going to meet the Jaguar spec. So, buy what makes you comfortable. The color has little to do with cooling ability, but more with what it is made from and whether it is toxic to animals, eco-friendly, etc.

As for how much, you will need a total of about 8 quarts of fluid. So, if you get a gallon bottle of concentrated antifreeze and a gallon of distilled water (try not to use tap water as this can have negative effects), then you are good. Or you can get 2 gallons of the 50/50 pre-mix and go that way. Up to you. The concentrate will be a bit cheaper, but it is more work on your part.

 

Oh dear! I flushed the system ok but now it only blows warm air. And of the 6 switches on that panel, only the fan is now working. No a/c, recirc or heated rear screen.. HELP!!