I got my 1993 XJS registered today, which I found out meant that I had to get insurance for it first, and had my new tires installed! I took them off and put them in the truck, not wanting to trust an untested car for an across town trip. I got home and put it all together and decided to take it on it first real road test! I drove it around the neighborhood 3 times just to verify it first, I had the top down, then of course, it started raining so I put the top up. I pulled out onto the main road and it seemed ok! I got to the stop sign in town, behind a newer truck and when I hit the brakes it acted a little funny, and the abs light flickered. Ok I didn’t like that, but the pedal felt fine, so I decided to continue up the other main road to the one side road. I went to turn there and when I hit the brakes it was very spongey and it took a little longer to get slowed down. Drrrrrrrr! I said ok I’m just going to take it home. I went slowly and when my next turn came up I had a car behind me, but I had slowed to 15mph. I hit the brakes and the pedal went to the floor and I rolled past the road! I pulled to the side and put on my hazards. Everyone went around and then I backed up and took the turn, running my hazards the whole time. I came to my next turn, and absolutely no brakes! I drove up the road until there was a little place to pull over and it was raining steady at that point. I called the wife and let her know what was going on. When the rain slowed I got out and looked around, but didn’t see anything wrong! I got back in and someone pulled up and asked if I was ok, then he said “yeah I had a triumph in the 80s! Brakes were horrible in it!” Then a guy buzzed through between us and he said “people that have never owned a British car just don’t understand” lol . I had pumped the brakes a little and they felt like they had pressure again so I figured I’d try for home. With the hazards on of course, and riding 2nd lol. I made it home safe! I don’t see any leaks, bit did notice that my right front wheel was smoking hot, so I figure the caliper may be locked. Drrrrrrr! Any ideas? Both the brake, and abs light would come on when I held the brakes in if it helps

 

I just checked and if I pump the pedal 25 times or so, then turn on the ignition, the pump runs for about 15-20ish seconds. With the car running, when I hit the brakes it runs for a second or so.

 

Hi Timeisrelative

My first thoughts are the same as yours 'Stuck Caliper' or a 'Stuck Brake Pad' which can have the same effect as a Stuck Caliper and have also had the same thing happen to me

What happens next, is that your Brake Fluid will boil and you'll lose all your Brakes, which in turn will do strange things like making your ABS light come on and all sorts of weird stuff like that

Very unlikely to be an ABS Problem, just sort out the Stuck Caliper or Stuck Brake Pad and all should be ok

Stuck Brake Pad made my Brake Fluid Boil and I lost all the Brakes (and how I fixed it including Photos)

 

Hello Time

This might not have anything to do with your problem - especially with your front wheel being hot

But - going through the history of my 1980 (without abs) the previous owner (x2 at least) was driving along and put his foot on the brake - no brakes at all.

Turned out that the "brake fluid was contaminated and has dirty discolourization".

No other work was required to get her back on the road (according to the docket)

This is also covered in the Palm book with the reservoir degrading over time

I think this must have been the last straw for the previous owner (x2) as it happened June 2018. The bloke I brought it off told me he owned it for 3 or so months, and it became mine in September

Doing the reservoir upgrade is on the "to do" list

Cheers
Steve

 

Steve
While a good idea to change fluid etc etc, the other advice you are suggesting is not relevant to the ABS cars. The problem is nothing to do with the reservoir - that is a non-ab only fix.

 

Hey Timeisrelative, I would check a few things, I,m no genius but if you have not lost any break fluid, you should not have a leak, I am pretty much leaning towards the ABS or the master cylinder check these videos out. Hope this helps,

 

There is a lot of misinformation here.

Firstly, ABS cars don't have a vacume brake booster/servo. They use a pressurized system utilizing a pump and an actuator (not a master cylinder). So no vacume leak or booster issue.

First things to do:
1: Replace pressure reservoir. The black ball. You should be able to hit the pedal several times before the pump comes on. The pump running time is totally okay.

2: Check the brake fluid level. Even with no light on, it can be low. Remember: it is a British car with British electrics.

3: Replace the brake fluid as per correct instructions (front nor ally, rear via pump running).

I personally think you have badly contaminated brake fluid i. e. too much water in it. Also the accumulator is dead.

 

Ok so even with it running when you hit the brakes it should take a couple presses before the pump runs? I have seen several posts where people change to the later abs setup, but there is so little info in the posts that it makes it hard to see if it's a practical swap or not. I have seen that the "newer" setup kept the back brakes working, even if the front stopped working. I REALLY like that idea! Lol 😁

 

Yes. Even with the engine running. The pump wasn't made to run constantly. About somewhere around 7-10 brake pedal strokes should trigger the pump pressure switch. Can be as low as 5 but it should start at 1 or 2.

The XJ-S and XJS got a total of 3 brake systems:
1: brake servo, no ABS
2: ABS with no servo (1988 to about 94/95)
3: ABS with a brake servo (about 94 to 96)

The ABS-free system is good but in an emergency situation a bit of an issue for modern drivers. The no-servo ABS works and is easily repairable. All parts are still commonly available. Just the actuator and block are rare and hard to come by. The parts inside are standard though. The last system of course is the most superior. Though I found it lacks the braking feel of 1 and 2.

Oh, all 3 systems keep brakes working if one set fails... Dual circuit brakes are standard

 

HI Daim,
I am respectfully not sure that what you are saying is entirely true. The later facelift cars that use the vacuum boost system still has ABS. (my 95 happens to have the ABS light on and it's probably a wheel speed sensor). ABS, to release or modulate the locked wheel, which is independent of what ever system is used to boost the pressure for braking, accumulator or vacuum. Both systems still use a master cylinder, which I guess could be called an actuator too, to convert your pedal pressure to move the column of fluid to the wheel. The ABS part just ports the closed off or released fluid that was diverted away from the wheel that was locked, back to the reservoir via the ABS pump. I think what you were trying to say, was that the system using the accumulator uses a pump to continuously replace the pressure that is being used to push fluid to each caliper, rather than use atmospheric pressure in a vacuum system to assist. When the pressure switch that monitors the system falls below a certain psi, the brake pump pressurizes the accumulator ball again, which pressurizes the total system waiting for the next brake application. Now that is a typical accumulator/pump system operation..and I could be totally off with the Teves system. I just commented because with my Vacuum system in my 95 I do have ABS.

 

Unfortunately what I've been seeing is that with my type abs setup, if the fronts fail, you have no brakes. Multiple sources have said this, on quite a few threads. It works when right, but when it doesn't, look out! Lol

 

Ok so I checked and all of my solenoids click when 12 volts are applied, so that might be ok. I have parts ordered, just have to wait on them. One of the biggest drawbacks of a Jaguar! I can't "just go get" what I need. Smh! And on that note, I was looking into something that I saw in a picture I took yesterday before my ride, and noticed that it looks like my subframe mounts separated on the ride! Argh! The wife's not going to be happy! First pic is from yesterday, I wanted to check the "gap" at the front mount. Second pic is from today. Smh!

 

I should have specified, that the 88 to 94 cars don't have a brake booster aka vacume booster as the earlier non ABS have and the later ABS do...

 

I think I'm making myself half sick trying to figure out what I want to do! Part of me wants to just fix the system as is and go with it, I have found that my pump runs with every push of the pedal, so my accumulator is probably shot. Drrrrrr. So that's another couple hundred to throw at it to see if that helps.
However, I don't like the whole idea of if something like this happens again, I have no brakes! I've had brake lines blow on other cars and it was much more manageable than this was!
I have seen that the xj6 setup is pretty much a straight swap, however when I look up parts, I see that they have the brake and gas pedal assembly as one, so apart from tearing it apart and reassembling it to fit, I don't see how it'll work right. I've also seen about the teves 4 setup, but I'm not sure if you then loose and function or not. Some threads alliterate that you only need the pedal box, booster and master cylinder, while others kinda make it sound like you need all that plus the pump, computer and brackets and such!
Sometimes I wish I was working on my older cars lol!

 

Do not drive the car until that is fixed

 

Oh absolutely not. Lol 😁

 

2nd drive today! Replaced both front calipers and pads, as well as new front brake hoses and of course the accumulator. I also replaced my rear sub frame mounts! Overall not a bad days work. My only concern is that, of course now it happens, the temp seems to be running higher than I would like. And by that, yes, it's up pretty high. I guess I'll start with the thermostat and new coolant to see if that helps.


Just thinking about it, I don't remember hearing my electric fan. Hmmmmmm

 

I did some research and found found threads saying about hooking up the fan to the ac relay. I remembered seeing a wire and went to try. Sure enough, the fan started right up! On the downside, it was sitting for almost 3hrs and when I hit the switch my temp needle went all the way to the right! I mean parallel to the top of the dash! Now I don’t know if it’s actually that hot, or if my gauge is just faulty

 

So my needle actually got stuck past the H mark. So I tore into the instrument cluster tonight and when I got it out I noticed that the needle was actually hitting the wood grain. I popped it open and it went to the wrong side of the needle! I realized that if the needle goes so far it will not go back without being pushed past the mid point. I don’t know why mine did it yet, but am looking into it. However, I decided to mod my gauge so it won’t happen again! I added a second pin well past the H, but not far enough to make it go to the other side. We’ll see how it goes, hopefully I’ll never need it, but it would suck to get it back together only to find it do it again!

 

Ok so I went out today and put my cluster back in. I started the car and within a second the gauge went to hot. I pulled the two wire temperature sensor and wiped it off, then cleaned the terminals and connector. I then realized there is a single wire sensor behind the first sensor. Is that the one that the gauge reads from?














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