Looking for some help with this, 2005 VDP, when I have the heat on using the dash vents, the passenger side blows hot air but the drivers side is only blowing cool air. Seems the same if the air is directed into the footwells as well.

Since it gets down to -30 C here, having a fully functioning heating system is kind of important.

Any help would be appreciated, Thanks
Paul

 

Of the many posts about the subject, my 2005 XJ8L was showing the same symptoms.
In my case, the heater core was the culprit and needed to be replaced.
Most with the same problem are finding the same thing.
Good luck with yours.
DAVE

 

Heater core replacement or a flush. Neither sounds easy or fun, does anyone know of a good write-up? Looks like we're facing this on our Jag too. If these cars weren't so trick looking and didn't ride so well....

 

This is a common problem with Jags. I just had the heater core replaced by the dealer on my 2004 XJ8 and now hot air blows through all dash vents.

There are several threads on this subject but the one I started recently is:
https://www.jaguarforums.com/forum/x...orking-105956/

At first I thought it might be the blend doors in the dash but the culprit was the heater core. From my reading on this forum it seems that a heater core flush doesn't always solve the problem, especially long term. Just bite the bullet and get a new heater core installed. It ain't cheap … about $1,300 if done by the dealer. It's COLD where I live and my shop is not heated so I let the dealer do it. It's not an easy job.

Your problem might be something else, but mostly likely it's the heater core that is clogged with gunk that directs hot air to the driver's side. Why it seems to always happen on the driver's side is a mystery to me.

 

What really gets me as a chap who did chemistry at school and university, is that nobody seems to have thought up a chemical flushing agent that will dissolve the crud when a reverse flush is done. Why we have to put up with an expensive replacement, I don't know, there should be riots of freezing cold Jaguar owners outside the factory !! (OK, only joking, I know we are all sober and law-abiding guys, except for speed limits !!)

 

Thanks for your replies all. Might try the flush first as $1300 is pretty steep, and I don't have the time right now to tackle it myself.

Cheers

 

 

$1300 sounds a bit expensive! The heater core is listed on the SNG Barratt for $188.42 and it shouldn't be more than 3-4 hours labour to change, a lot less if you know what you are doing. Looking back through the bills for my old X350, I paid around $250USD all up in 2010.

There are a few things to disconnect under the bonnet, then you have to remove the glove box and blower motor.

 

I think it is more expensive here in the US as the steering wheel is on the wrong side. As I understand it, that means the dash has to be removed!

I actually made a post a few weeks ago about doing a chemical flush with something like CLR (removed calcium lime and rust) just to see if that would do the trick...just haven't had time to try it yet!

 

Dash does not have to be removed. Glove box out, blower motor and blower motor housing out. pinch off heater hoses at firewall, remove heater inlet, outlet pipes (be prepared to capture coolant that flows out of core and pipes) and slide core out to the passengers side (lhd cars). Install is the reverse. Easy to say extremely hard to do if first time. Getting the blower housing out and back in is frustrating as h*ll ,need to be Sherlock Holmes to find the 6 or 7 mounting screws/bolts, hooking up the pipes to the core with the mickey mouse clamps and Phillips head screws equally so, little room, need small hands, multiple Phillip head tools. Best to find an indy who has done them before (more than once) I did mine myself and in hindsight would have gladly paid the 4 hours labour I was quoted. My heater core kit was about $180 cdn from the dealer,included new clamps and o rings.

Stu

 

Hmm, interesting info. There is an independent shop here in Regina that I will approach and see how much he would want. Thanks for the replies
Paul

 

To be clear, (some) heat on passenger side but not on driver's is a heater core issue?


I have the same problem and would not be surprised if my heater core is, in fact, clogged, as I recently used the ole pepper trick to plug and then locate a hose leak under the S/C. The recovered anti-freeze was filtered before being reintroduced to the system, but there was a lot of pepper still in the system.


Please advise.

 

That part makes no sense to me at all. If the heater core is plugged, the heat is marginal or non-existent uniformly. I do not see how it could possibly affect one side and not the other unless I am missing something....

 

As I understand it, the heater core plugs from one end, which happens to be the area that provides heat to the driver's side. It is strange how the two vents in the middle of the dash put out such different temperature air.

 

4 hours labor rnr and yes no heat on the drivers side is plugged core. The coolant flows in a crossflow "u" on its side. As coolant sits in the core and owners that dont get coolant flushes done because they think its hogwash, the bottom of the u collects sediment over time and gets gelled and solid. The bottom half or closed end of the sideways u feeds the drivers side, the passenger side is fed by the upper half or the open side of the u. Have cut open several to see this. Moral of the story, flush your coolant on a regular basis and i like to disconnect the heater core feed hoses and help the cleaning by blowing air through the core to help clean out the crud. You can try flushes after plugged but imo at that point i would just replace the core and move on

 

Great explanation Brutal, thank you.

Is there a recommended way / writeup of performing a cooland flush on our X350s?

 

Nice to see Brutal posting again. This is the first time I have read a description of what actually blocks up in the heater core. About time it was redesigned, I reckon !

 

I found something useful that might be of interest to this thread. I, too, was suspicious of the 'no heat on the driver's side is a heater core blockage' answer, but ...


I learned that if I select the dash vents only and then closed those on the driver's side, effectively only blowing air to the passenger's side, I could overwhelm the heater core. In other words, it wasn't too long before the temp on the passenger's side began to drop. Sure, while on the move the output heat level would come back up, but that I was able to effectively chill the core confirms in my mind that either (a) the core is blocked or (b) the auxiliary coolant pump is not operating properly.


My immediate plan is to attempt to flush the core. I understand that few have had luck with this, but it does seem the fiscally prudent first step.


I'll let you know.

 

Love it !! We must make you an honorary Englishman. Good luck with the job, and I hope it works for you.

 

Did the flush and there appears to have been no, zero, zip clog. Nothing blew or oozed out. Just clear flow both ways. Unless I don't understand the internals, I'm ruling out the heater core as the problem.

Okay, so all back together and double checked the auxiliary coolant pump. Rerouted wiring with a little less slack and seems to be working fine.

Coolant lines to and from the heater core warm up nicely, with the return line slightly cooler than the feeder. Seems the way is should be.

Unless someone has another idea, I'm going under the dash and am going to fiddle with the air blend door on the driver's side.

Please tell me I'm missing something.