Everyone loves driving an XJS, but there are a couple of key shortcomings that really detract from the overall appeal of the car. One of the more basic problems is the heating and air conditioning system- it just doesn’t seem to blow the right amount of air in the right places. The center dash vent (of the 76-92 cars) blows way too much cold air into the back seat (and not enough on the 2 front seat passengers), and the lower heating vents seem pretty wimpy. Here are a couple of simple fixes for these problems:

1) Center Vent-

Jaguar (after only 18 years of production) recognized the fact that the center dash vent blew too much air into the rear seat area, and fixed the problem on the with a new design vent on the 93 models. The old design had 3 sections- 1 large fixed center area , and 2 smaller (one per side) movable, directable registers. Due to the design, far more air went through the center then either end, so while the front seat passengers cooked, the rear area stayed cool (this is particularly comical as most XJS’ never ever carry a passenger in back…). Anyway, the new design vent eliminated the fixed center section and made the 2 movable sections larger, so appropriate air was directed where most needed. This new vent is Jaguar part number BEC-26361, and is basically compatible with at least the 82-92 XJS coupes, converts, and cabriolets. All that is required to install it in an older car is to remove 4 small mounting tabs on the new part and file 2 small notches in the dash. Either style vent is just held into the dash by virtue of the clips on the center dash wood. Carefully pry off the center wood piece (using a long screwdriver with the glove box open, and pull out the old vent. After removing the tabs from the new vent, place it up to the opening in the dash, and it will be obvious where the 2 new notches need to be made. A small file or Dremel tool make quick work of that. Push the new vent into the dash, replace the center wood, and you’re done. The whole process takes maybe 30 minutes.

Here’s a photo of the finished modification (this is on my XJSC)

2) Improving overall heating and cooling airflow -

You may not be aware if this, but the heating system in your 76-86 XJS is actually the very same unit that Jaguar installed in the 74-87 sedans (the 87-93 XJS’ use a different system housed in basically the same box, with the same openings/ducts). One of the key features of the sedan–based design was the provision of duct work to the rear seat for heating and cooling. These ducts ran from the AC/heat unit in the dash, through the console, and to a single outlet in the rear of the console, facing the rear seat passengers. All XJS’ used the same system, and the rear ductwork and outlet as well (the outlet actually directed air down and to either side of the rear of the console-not very effective) . As an XJS owner for over 10 years now, I can count on 1 hand (with only 2 fingers) how many times I’ve had passengers in the back seat (and that was with my coupe- there were never any in the cabriolet or convert since there are no back seats!!). Anyway, since this rear ductwork is redundant, and the Jag fans seemed a bit weak in general, I decided to remove it. Basically, I removed the console, and then removed the ducting tubes and rear register . I then closed off the lower fittings in the AC/heat unit with rubber plugs, and replaced the console. On convertibles and cabriolets there is nothing more to do; on the coupes a small metal strip needs to be added to the inside rear of the console to retain the rear seat center ashtray (not present on the other models). As a result of removing this rear ductwork, the air flow from the dash and lower heating vents is now much stronger, and the system appears to work much better overall. Another added benefit of removing the duct work is that there is now much more room for all of that wiring and such in the console, so nothing is pushed or pressed together, etc.,.This modification should work on all 76-93 XJS models (I believe the 93 and up cars use a different more advanced and adequate AC/heating unit and fans).

Here’s a couple of photos with the console removed and the lower fittings open, and then plugged (the plugs may look like they have holes on them, but they are each sealed on the other end).