Jaguar Forums - Jaguar Enthusiasts Forum - XJS ( X27 )

V12 1989 Oil leak drivers side

JAG747 — Sat, 23 May 2026 00:41:06 GMT

Hi all,

I own a 1989 Jaguar XJS V12 and it has a slow engine oil leak. I first checked up top around the oil senders and cam covers and everything looks fine.

Went underneath and couldn�t see much at first, checked the sump and then removed the torque converter cover and found this. It looks pretty fresh with new oil.

I also checked the PCV and it wasn�t too bad, but easy enough to clean.

Any ideas?

Teves ABS issues

BradsCat — Mon, 18 May 2026 23:18:23 GMT

All,
I have an '89 XJS with Teves ABS. It is not working. The relay is good. I have tired several times to bleed the rear brakes according to the specific directions without success. Moving deeper into the test procedures we tested the pump motor today. I have a spare from a '91 XJS and both pumps tested good. However the pump itself on the '89 appears to be kaput.

The units are not exact replicas of each other. The '89 has two hose connection to the pump housing. the lower one held in place with an elbow connector and a retaining lock pin. The upper one with a rubber hose with a bolt thru the top of the top of the metal connector The '91 has a brake line like metal tube in lieu of the upper rubber hose with with screw on compression connectors on each end. I will try to get these upper line connectors off but from a casual look they are different sizes and therefore not interchangeable.

Q; Can the actual pump be cleaned?
Q. Any issues with using the '91 unit instead of the '89.

what model was this fitted to

xjtom — Mon, 18 May 2026 22:23:09 GMT

what model xjs was the Lucas CEI ignition system with the AB14 amplifier fitted to??
Thanks
Tom

1996 XJS Celebration Imobiliser Fob

Dominic McGuinness — Mon, 18 May 2026 15:29:16 GMT

Hi - i'm looking to source an addtional imobliser fob (the one that you plug into the dash located port) we have 1 but feel better have a back up. Have the required code number. Any idaes?

1986 XJS Oil Cooler Return Hose

davidlorastein — Sun, 17 May 2026 20:51:14 GMT

Greeting,

I am sealing up a few oil leaks, one of them being the oil cooler return hose at the sump. When I took off the oil cooler hose at the sump I noticed there was no thread sealer or O-ring. The end of the hose where it connects to he sump fitting is flared. Is there supposed to be an oil ring in the sump fitting, it looks like there is one but its just old oil film and should I use some type of thread sealer. When I took off the fitting on the sump I did see an oil ring on that fitting where it attached to the sump and I have been made aware that the fitting needs to be centered when reinstalling.

93 xjs Climate control

Freddys — Sat, 16 May 2026 18:06:21 GMT

My cars climate control doors don't work. I have just checked the check valve under the bonnet, seems to be fine. Can someone please explain to me the use of the one control lever under the radio? Not sure what it is supposed to do.
I will be checking out other vaccum lines later today. Thanks

Still leakin water

vampgovegan — Fri, 15 May 2026 15:15:14 GMT

i sealed with silicon the windscreen seal and it worked well.
now i have a wet footwell again. Any suggestion?

Tachometer and cruise control erratical then not working

vampgovegan — Wed, 13 May 2026 11:18:43 GMT

Hello,
I've been reading few thread about this issue. I couldn't find something similar to what happened to me.
Mine is a XJS V12 HE 1985.
First the Tachometer started to work erratically and then died. This is happened in parallel also with my cruise control...
I find this strange so I'm asking my self if they are combined or if they just work together against me!

Evaporator replacemtn

Ginoxjs — Mon, 11 May 2026 20:40:15 GMT

Hi all first post here.

i would like to ask how many times i have to remortgage my house to get the evaporator done on the cat?

doesn any of you done it recently?

and do you know anybody that would do it around Surrey Berkshire Hampshire?

thank you in advance

Parrelel flow condenser upgrade

rgp — Mon, 11 May 2026 18:38:08 GMT

dead end

XJS Windows not working

StevieYonder — Mon, 11 May 2026 12:54:22 GMT

Hello fellow Jag enthusiasts

A fortnight ago I drove 15 miles in my 1991 V12 XJS to my "local" swimming pool. It was seven in the morning so I didn't use windows. After the swim I got back in the car, started up the engine and then tried the driver side window - no response.
Tried the passenger side - no response. On the journey back I noticed this clicking sound - sounded more like "tonking" coming from under the glove box. I arrived home and after some research realized this was the thermal cut-out fuse. The noise occurs as soon as the ignition is switched on and starts immediately and occurs every 5 seconds or so ( whether you operate window switches or not) . The cigar lighter and mirrors all work but the windows are dead.

I took off both window switches from the ski slope and then turned the ignition on - no "tonking noise". Mmmm - fitted two new switches - "tonking" starts again. Fitted a new passenger side switch and tested with no driver side switch fitted - "tonking" starts,
Fitted a new driver side switch with no passenger side switch fitted - Bingo! The driver side windows worked and no "tonking noise".

Having narrowed it down to the passenger side I am not sure what to do next. The passenger switch is probably not the cause of the problem as I fitted a brand new one so the fault must lie downstream from the switch. Do I have to take off the passenger side door card? Has anyone had these symptoms before?

One possible clue to all this - I did take a left hand band faster than normal on that drive to the swimming pool - maybe that caused a wiring issue?

Help with a decision ... plus XJS progress

BenKenobi — Mon, 11 May 2026 10:04:47 GMT

Not strictly XJS related but I trust the folks here ...
I intend to move the current daily on as I really don't drive a lot, so instead of the S4 Audi I have the potential for two cars both at opposite ends of a spectrum, I DIY all maintenance and don't give a fiddlers about mpg ...

A 2007 Porsche 997.1 - a little fun box but potential major money pit - the car is however in need of a lot of TLC

A 2004 BentleyArnage - a huge land yacht but also a potential major money pit, requires nothing except fuel ...

Both cars are ironically black, utterly impractical compared to the S4 Avant but I'm tired of modern computers that rule every function, and want something a little more 'old school' ... what does the team think I should choose - S'P'ort or Sno'B' -

For what it is worth the XJS is progressing, the rear inner arch is now fixed, all painted inside and out, same goes for the drivers side floor pan that I had to beat straight (inappropriate jacking by previous owner). Currently installing the Dodo mat, the cam covers and manifolds will be in place and bolted down by the end of the week - oil pressure proven - sump filled no leaks .. new ground straps made but power steering lines removed again - I really cannot deal with how they fit - that's a work in progress. I've also dropped the exhaust again as I cannot get the rear subframe over pipes to play ball - fouling my easi bleed but also if they're in the mounts how I'd like them the back boxes won't fit - and those are a tight fit too. Need ten pairs of hands to hold it all up, it is like fighting an octopus except it is overhead and heavy.

I've had to rust treat the platform that the fuel tank sits on, that needs paint finishing, close now to getting the wiring re-instated for the Emerald ECU. I have a bit of a challenge on the harness in terms of how I get through to the engine bay, I'll be following the original harness route but I need a better connector type as there are a lot more wires to hook up - the connector for the engine bay harness to ECU harness I haven't found yet I need around 48 connections - 36 minimum. I haven't figured out the internals yet i.e. oil pressure and temp sensors but these are only for the gauge cluster, I'll need a dedicated connector for the crank position sensor - no getting away from that shielded cable ...

I'll get a pic of the arch and floor repair before I apply the Dodo mat.

Brake pressure delay valve

CS_XJS — Fri, 08 May 2026 09:43:59 GMT

Car is a 1995 XJS 4.0 with the Teves III powered system for the rear brakes. I seem to have brake fluid weeping very slightly from the rear brake pressure delay valve located on the RHS inner front wing underneath the power steering reservoir. To test if this was the leak I wrapped the valve with paper towel held tight with lock-ties, put a wadge of paper towel between it and the PS reservoir. drove the car, used the brakes hard and sure enough the paper towel around the valve was now damp. Also I recently replace the power steering hoses and reservoir and cannot detect any fluid leaks from these so I'm pretty sure the pressure delay valve is weeping through the O ring.

I think the fluid is weeping past the O ring (I have checked the brake line connectors for tightness and in my test the area around the O ring was the most damp) but from researching the various threads on this forum I don't think the O ring is a seal, rather a way of stopping contamination getting in through what looks like a tiny vent hole.

Is there any way I can test if the valve is functioning properly? The valve can be split but all that does is reveal a small chamber and no obvious way of getting into the actual mechanism to examine and / or replace seals.

I have a spare valve but without knowing how to test it I'm not sure if fitting it will make my problem better or worse.

Any ideas, thanks.

As a plan B I guess I could replace it with a 3rd party proportioning valve, does anybody have any experience of this?

90's radio code factory settings solution

Steve Lockwood — Thu, 07 May 2026 21:52:51 GMT

For those of you who like original equipment and have a radio without a code and want music while working on car, here is the fix on most to set code to 1324. there is an access under label where there are solder connections, the 2 solder connections determine the code. if you break the 2 solder connection the code is factory 1324. If you have a radio out and know the code, post the connections that are soldered and the corresponding code so we can make a cheat sheet! Time to load the CD magazines and jam while I work! Found this at https://carstereohelp.com/stereoremovalJaguar.htm

Rebuilding power window motor

Rchuda — Thu, 07 May 2026 17:39:53 GMT

Does anyone have a resource where I can get 1994 XJS convertible power window motor rebuilt? I am Leary of buying a used unit that could be 30 years old and not much better than what I have.

I am in the US.