I'm working on totally upgrading my interior details and while I have the dash trim pieces off, I want to deal with the rear air ducts.
I saw some where that the two air flow tubes running down the center console to the rear floorboard can be cut and capped off, greatly improving the front flow.
WHAT??? do I cap them off with?? I also seem to remember a photo of this mod and it looked like rubber plugs but now I can't find the info.
I did find the later model dual vent for the existing crappy vent I have now. You know, the big center opening with two worthless adjusting vents!!
Has anyone else capped off the rear ducts??

 

As I recall the rear vent outlets are rather small. You could probably plug 'em off easily using ordinary household caulking or similar.

Others will chime in.

Cheers
DD

 

I have to disagree with the philosophy of blocking these off. The rear vents exit to the lower side at the rear of the console and provide air flow up/against the driver and passenger but not truly to the rear of the car....your vehicle should be cool in the summer and that is accomplished by "distributing" air throughout the cabin not just blasting it at your front side. I'm trying to drop the temp in the cabin where I'm sitting not just "wash" my front side in cool air. That being said I did replace the worthless center vent with the X-J40 one and that in and of itself does wonders to direct some flow over either the driver or passenger.

 

JT, I agree with your rationale but, in my experience, it works well for heating but not so well for cooling. I found that the inside of the console captured so much drivetrain heat that the refrigerated air was barely cool-ish by the time it exited the ducts.

<shrug>

I never blocked of the rear ducts on my XJS but it was something I considered from time to time.

As an aside I'll mentioned that my Ser III XJ6 had clever on/off controls for left/right/center rear ventilation. Very helpful. No doubt Jaguar anticapted far less rear seat use in the XJS and deemed such controls unneccessary.

Cheers
DD

 

Probably wouldn't hurt to wrap the pipes with insulation similar to my AC run in my attic...that to me would be a more efficient use of air distribution then simply blocking them off...ah, yes, another XJS project. It will have to take a number!

 

Good idea on the insulation !


Cheers
DD

 

I'm looking into this as well, but it's only going to work if the flaps are in an appropriate position. If there's not an even enough gap between the dash and rear foot-well outputs, it's just going to build up heat.

I'd personally like to get rid of the front and rear foot-well vents. This '96 has the most obtuse climate controls I've seen.

Nothing seems to do what I want. The air pressure is wonderful from the windshield vents, but when it's set anywhere else it's highest at the foot-well vents, leaving the dash vents a bit ineffective.

I've got a temperature knob on the left, and a temperature slider on top. I've been told it allows a different temperature between the dash and foot-well vents. I don't know. I'm not sure which does which, but it doesn't really matter, as the cabin is so small the difference would be irrelevant after ten seconds.

I've got a manual button. Doesn't seem to do anything. Demist? Not sure what that's affecting. Recycle seems to work, and so does the air conditioner button.

The fan control knob on the right has three power levels and, oddly enough, the full power windshield vent setting. The only thing I can really tell it to do is blow on the windshield, because any other setting just seems to give it a choice to do whatever it wants...

So, yeah. If I can block the foot-well vents and get the air coming out of the dash, I'll do it.

Honestly, though, I wish I could just swap that stupid climate control junk for something simpler.

 

I'm not familiar with the version of climate control fitted to the very late cars but my gut feeeling is that yours isn't working correctly.

FWIW, on the earlier versions......

When heating is called up almost all the air would come from the footwell vents with some from the dashboard end vents. When cooling is called up almost all the air should come from the center dashboard vent with some to the footwell vents. In other cases..."blending"...air should come from both footwell and dashboard end vents.

I too would be perfectly happy with a "manual control" ventilation system. Basking in automatic luxury gizmos is cool and all that but I think I can manage the momumental effort needed to manually adjust some controls :-).

Cheers
DD

 

I absolutely hate automatic stuff like that.

I'm sure it all made sense to the guy that put rear foot-well vents in a car with unusable rear seats, though.

I'm going to go out and try the air conditioner and the heater alternately to see what happens, and play with all the buttons. You might be on to something.

I wish this stupid thing had come with a manual.

 

Hi Phil. I think this is what you are looking for, Jaguar Specialties: Tech Tips 2
Done it myself. Used plastic caps off shaving cream tins.
Very effective as I own a Cabriolet (without rear seats) so all that air was being wasted. Prob about a 30min job.
Regards, Rod.

 

A 10.5 rubber stopper is the right size.

I used a bit of silicon to hold them in. I had the ski slope out anyways so went ahead and plugged up the ducting to the rear. Just be careful pulling out the ski slope as it's easy to chip the veneer.

Cheers,

- Will

 

Will, I see your in Jacksonville but haven't seen you at any JCCNF club meets/events. Check jagdriver.org...like to see you there.

 

Someday, when I have plenty of time I am going to remove the car from around the heaater/ac unit and see if manual rods. levers. bowden cables can be put on some of the ac doors in there. Wish me luck.
RagJag

 

On my '94, which should be very simuilar to yours, I found the rubber ducting inside the dash had worked its way loose to the point where only about 50% of the flow from the blower was actually finding it's way to the dash vents. Once I fully reconnected them, I had all the air I could use. In fact, once the outside temp dropped into the 90s I found I would keep the air speed on low. Check those rubber vent tubes. There are no clamps, simply pushed in place (similar to the cold air intake setup under the hood). It only takes about 3 minutes to do so. And, if you can not see under there, have your fan on high so you can feel the air escaping so you know where to focus your efforts.

Good luck!

 

On a similar but related note, I noticed on my '94 Coupe that when the AC is on outside air, there is positive pressure in the car because there is no place for the air to escape. If you lower one of the windows 1/4", you can hear the blower speed up with increased air flow from the dash. I thought that the small black plastic grills mounted on the B pillars below the door strikers was supposed to relieve the pressure but since they are mounted on the outside of the door gaskets, they are blocked off from cabin pressure.
Has anyone else noticed this? My '94 is one of a small group of coupes that does not have a recirculate button on the AC control.
Would appreciate hearing from some of you about this.
Thanks.
Take Care
Bob (Spillwaybob)

 

If the A/C cold air flow to the rear is lukewarm by the time it gets back there, then isn't that air flow providing a benefit by taking away some heat that would otherwise be against your leg and seat?

 

My '92 rear pipes are capped off from the factory. They just about reach to the front of the gear lever. I was going to extend them to the back as in the newer cars to improve airflow. . .

 

Your car was 2-seats only when new, wasn't it? I'm just wondering if that's why the vents don't go back there.

It may be because I don't need as much cooling as drivers in the South but I find the factory system (with rear vents and the big centre vent that seems stupid but kinda isn't) work well for me.

 

Good luck! Yours will be the first Steampunk XJ-S. Could be interesting.