Hello again, per my previous post, my driver's side heat isn't as hot as passenger side. Mechanic reverse flushed cooling system to no avail. He's pretty confident that it's a blend door problem but we haven't discussed estimate yet. Anybody have experience with this type of repair? Time and cost involved? Many thanks. 2005 XJ8 VDP.

 

There have been some blocked heater cores reported, this is in the archives. The casting sand from the blocks gets in there and plugs half of them. Sounds weird to me but this seems to be the case.

 

Here is a "How it works" from the X350 shop manual. It looks like the one core has two sections, so one side of yours could be blocked.

You didn't say if this is all the time or just at low speeds and idle. If if gives normal heat at higher engine speeds; then the aux coolant pump isn't working.

 

ok again I answer same issue. did he blow it out first? I have cut many cores open(theres only one) and the drivers side portion is on the end loop and gets plugged with sediment from the cooling system(never found sand). If its been flushed and blown out, you need to replace the core..This issue comes up EVERY yr when it starts to get cold and people use the heater again after a summer of non use.

 

It is badly worded but I think that just means that the heater core straddles the air intake for both sides of the dual zone unit.

There isn't a hot water shut off valve on the X350 so hot water circulates through the matrix all the time so there is little point having dual cores.

Air temperature is purely controlled using the blend flaps enabling driver and passenger to select their own temperatures.

 

I had the same problem, heater core had to be replaced. The core itself is not that expensive but unfortunately it requires eight hours labour which increases the cost quite a bit.

 

I remember reading about replacing the heater core in a Fox bodied Mustang and seeing photos. It entailed dropping the dash assembly. Does anyone know if that is the procedure for XJ heater core replacement?

 

In this part of the forum X350 etc. go to: https://www.jaguarforums.com/forum/x...k-links-20085/

Go down until you see the part about workshop files and download "Electrical" and you will find the info about replacing the heater core there.

I would try putting something that vibrates against the pipes and see if the blockage will shake loose. Call a plumber and see what cleans out copper pipes.

 

As cold weather has finally come to North Texas, I have come to the conclusion that my car is suffering from the same malady as Anxious Jim's car. I have exactly the same symptoms he describes, with the driver's side noticeably less warm than the passenger's side. Some intuitive "best practices" kicked in. I began cycling the airflow speed and direction, putting the ventilation system "through its paces", i.e., floor only hi/low speed, floor and a/c vent mix, hi/low, defrost and floor hi/low, etc., with a/c w/o a/c, recirc./not recirc., system set to "dual", system set for both to work in together, etc, etc, every combination I could think of.

This has brought the system back, over a period of a couple of weeks, back to where the temperature on the driver's side is once again very close to the passenger side.

 

I am having the same problem vary little heat on driver side 2005 xj8L

 

Hello my fellow Jag owners. The heat is weak on driver side. Any info will do THANKS

 

Search uk forum for details of heater matrix (core) cleaning done using (I kid

you not!) "Steradent" ie denture cleaner.

 

Mine has been partially plugged for 2 years. The 2nd winter I had the car I had no heat at all. Here is what I found.... The main problem was the auxiliary electric water pump (below coolant reservoir) This feeds water through the core, mine was shot and non functional. (no Flow) Dealer wants $400+ for the part. They can be found on ebay for $80 or less. It is the same pump that is on a 02' VW jetta 1.8 turbo. Once I replaced that and back flushed the core (with no chemicals) I had heat everywhere except the drivers dash vents. Thats the way it has been for 2 years. I am going to try and flush it with CLR or denture cleaner and see what happens. I talked with a Jag tech of mine. He said that the foam insulation on the blend doors can deteriorate and fall on the core blocking airflow. He also mentioned that the core can be removed with little effort by removing the glove box, cutting the steel pipe, and making a joint with rubber hose once the new core is installed. If the chemical flush doesn't work, this is what I am going to start with and verify that it can be done this way

 

Had the same problem on mine. Backflush didn't work.
It needed a new matrix which meant having the dash removed. Big job!

 

I just came from the Jaguar dealership in IA today regarding the same issue. According to the mechanic, the blend doors can not be repaired and the entire heat/cool vent section in the dash has to be replaced. The cost is $2100 for the part plus 4-5 hours of labor.

 

This is not true, replacing the heater core is a 4 hr labor job that requires removing the glove box and fan housing only, not the dash. I have not heard of needing to replace the whole housing either unless it was damaged in a collision. The blend doors and electric motors are very tough and designed for a long life. I would also mention that there are two temp sensors in the outlet air duct that control the system , so be sure you know what you are working on. I suggest getting a trusted pro to deal with this but protect yourself from wholesale replacements, the core is not hard to replace.

 

I meant to mention that the outlet temp sesnsors are for left and right, so if one is not working right, it can affect the temp on that side, so get the codes pulled and get the diagnosis right before tearing into it.

 

Looking at the woes of heater matrices from afar, (300 miles at least !!), it seems that the V8 engined cars are particularly prone to blocking of the heater matrix. It is almost never reported on the V6 petrol engine, nor the diesels sold in Europe and the RotW.

 

I was intrigued by your statement so did some research and couldn't see any obvious reason for this but after a quick look through the UK forum I did discover that the V6 is actually the one that has the issue the most, possibly because they are the most common of the petrol engines.

I found 11 V6's and only 4 V8's of various flavours, one of which was mine

It was only a quick search but I didn't spot any diesels so may be something changed from '06 on or they just haven't got to the point of blocking yet.

 

I had the same problem with my 2005 XJ8L. I was quoted $3247 to replace the heater housing (part cost $2100). However, when they started to tear the dash apart, they realized the housing was OK (all blend air doors were working properly). Instead, they replaced the heater core for $1300. I now have warm air flowing to the driver's side of the dash.