Hello. Hope I am posting in the correct area, I am still new here. My 1989 Xjs developed a problem today and while I search the considerable archives of this forum, maybe someone already knows the answers to my issue, and can save me some time and eye strain.

I bought the car two months ago, lots of receipts, took it into Viking motorsports in Orange county Ca, and they inspected the car and fixed a few issues. Alot of recent work was done to the engine by the previous owner, so all the motor needed was a fuel injector hose kit including new mounting rings. After this the car idled slightly rough, but ran perfect. The car hasn't been driven for a month since then because we moved, and the car was transported, and I needed to deodorize the car since there was a fuel tank leak.

So I drove the car today,to make sure everything was good for a 5 hour round trip drive to and from the airport. It felt perfect and was a pure pleasure to drive. On my return I got on it a little bit, I floored it from 25 to about 60, was quicker than I expected. I got home just fine. My wife got in the car, and as she pulled away I thought I heard the car hesitate or almost stall, and chalked it up to my imagination. A couple minuets go by and she calls telling me the car wants to stall. As she limped home I got behind her thinking she might not make it and I could smell a bad smell, exactly like a clogged catalytic converter and saw a puff of smoke out of the right exhaust pipe. Smoke looked grayish blue like unburned fuel. The smell is like sulfur, a little like burning plastic. Car was running rough and I shut it off. tried to start car a couple minuets later to pull in the garage and it wouldn't start. There was a little bit of smoke in the engine compartment by the firewall, there is a sloe oil leak back there so could be that.

A little back info on the car. 1989 XJ-S, V 12 90K well maintained. stock.

Any ideas, or suggestions would be greatly appreciated. I have slightly more than basic mechanical skills. I almost passed out when I opened the hood and saw the motor. This is my first jag, and that was my first real drive in the car since my test drive, and driving it home gasping on the gas smell from the gas saturated trunk carpet and padding.

Keeping my fingers crossed hoping this isn't going to be the standard of my drives in my new to me XJS.



Thanks in advance.
Brent

 

marelli failure. please fix before you drive it anymore.

Tip: The first thing i bought was my XJS. the second thing i bought was a fire extinguisher.


dont feel bad. i made it 50 miles in my XJS before the radiator hose blew and left me stranded, and once i got it home, it stopped running well enough to even drive.

 

The first thing I did to the car was add a fire extinguisher.

My 89 has the Lucas ignition. I beat the midyear changeover to Mirelli by a few thousand cars. I guess the ignition is a good place to start.

 

I have Marelli and 2 fire extinguishers

Sadly I have found a lot of the problems on my XJS were from a PO trying to "fix" something. I'd go back and start looking at the work that was done on the fuel injectors. All the interesting ignition parts are in the middle of the V too, so if there's been someone in there, there's always a chance a wire has been loosened, etc

As M90 suggested, your issue sounds to have exactly the same symptons as the classic marelli failure/cat fire, which means unburned fuel getting into a hot catalytic convertor, so yes, its pointing towards a lack of spark on one or more cylinders and/or a stuck open injector

Don't be afraid of the engine...... it's why you bought an XJS in the first place :-)

 

wow. that 5.3 just mooned me with its beauty.

i wont be able to look at mine the same for a while.

 

@M90

Mine ran on 7 cylinders when I first got it, and it's been on fire twice since...... stick in with yours, you'll get there

 

are you talking about the same one thats in that picture?!? holy cow. if thats what a fire makes your engine look like, by all means, set mine ablaze! lol

 

Ocean, I'm going to throw this out there for consideration. Since you don't have the Marelli ignition, my next guess would be you have a couple spark plug wires crossed, especially since someone had worked on it. With the V12 it would/could still run okay, but slightly rough. Since it isn't burning the fuel in 2 cylinders, it could have dumped raw fuel into the cats and caused them to melt and plug.

It's easy enough to check, the firing order is listed on the airboxes. Might be worth the time to check it out!

 

Thanks for the suggestions, it's raining here and the jag didn't make it into the garage so I'll have to wait to check these things. I guess this is a good waterproof test since the car has been garaged since we bought it.

First thing I'll check is the wires, it was idling rough and running real smooth so probably isn't the wires, but an easy place to start. I'm leaning towards one of the coils failing since it seemed like one bank wasn't' firing. Really hoping carts aren't melted though. Anything obvious I should be looking for?

 

@Ocean

If this is your first V12, it can be very deceptive if you are not used to it. As Jamey said, even 2 crossed plug wires and running on 10 cylinders could appear to be "running real smooth". I lost one half of the engine in my Marelli incident, and even though I was completely aware of this potential issue, I didn't connect the dots until later (when smoke and flames appeared) because the car certainly did not feel like it was only running on 6 cylinders.

When you say rough idle, is it lumpy ? or the idle speed is just hunting up and down ?

For your cats, what I found after I had really BBQ'd one of mine was that if I revved the car at standstill, bits of the cat honeycomb spat out the back..... I assume this would be called a total failure :-) The car subsequently failed smog badly on that side and I had to replace the cat (did both actually)

 

if its a Lucas system, the second coil isn't going to affect it much. They're wired in synch because they didn't have the technology to make coils that could produce a fast enough spark for a V12 above 3000rpm. You most likely have crossed wires, a bad plug or 2, or they put injector wires on wrong cylinders

 

After two days of running down the battery trying to start the xjs, it started right up today and I was able to put the car in the garage and quickly shut it down. Now I can finally check out the suggestions made from forum members, raining a lot here. I have to say the fuel injection wires makes a lot of sense since I just had new fuel injector hoses installed.

For the last two days when not trying to start the xjs I have been searching for engine schematics or diagrams showing the wiring, fuel injection etc.. on this forum and online. I am coming up with nothing.

With the purchase of our 89 xjs came a Chilton or Hanes manual for up 87 xjs. I discarded it as being a Hanes or Chilton and it was the wrong year, and in the process of moving I stuck it in a random box thinking it would be at least a year before I had to do some wrenching on the car, because of all the recent services.

So now I have been desperately looking for that manual with no success. Does anyone know of any schematics that I can download or at least view on a web site?

Thanks for all the feedback so far.

 

This should get you started. http://captainjaguarscathouse.com/El...ec%20Guide.pdf

Do yourself a favor and order from JDHT.com or one the Jaguar suppliers the DVD for your car.

 

funny, my XJS wont rev past 3k.

could this be why my V12 loves the timing?

i tried unplugging the secondary coil and it made no difference in the way it ran or revved.

 

After posting this problem last month, and after an injury which prevented me from standing on my foot, I finally got to looking at everything suggested.


All the spark plugs looked like they were in the correct position . While checking the wires I found that the vacuum going into the top of the distributor was broken off. There was just the hole where the white tube the vacuum lines hooks to.

I took the distributor cap off and there was the rest of the broken white tube in pieces around the distributor. I got the cap off but can't get the rotor off, am I missing something? In the past on other car I just pulled up to remove the rotor. While searching this forum about distributor stuff I came across someone mentioning that the rotor should snap back after twisting the rotor. My rotor doesn't twist, let alone snap back. I'm afraid if I pull to hard something will break.

Am I missing something obvious, or is something really wrong with my distributor?

Brent 1989 XJ-S

 

The rotor should pull off the same as any other car, its probably baked itself on. It may take some effort and may not come off in one piece, but they're cheap to replace.

Yes, you should be able to twist the rotor easily about 1/8 of a turn and it should snap back. If it doesn't, the centifuge weights are seized. A common problem with these cars. The easiest way to fix it is to remove the distributor and disassemble it. Lubricate it with graphite spray, not an oil because it will collect dirt. There are 3 allen bolts that hold the distributor in underneath the plastic shield inside.

Mark the distibutor and where the rotor is pointing before you remove it so you know where your timing is!

 

If it was swapped leads then it would have had the issue all the time i would expect. Are you sure it is Lucas? my car is early 89 and has Marelli easily identified by the 2 orange ignitors on the radiator support..

If it is Lucas would look first for loose plug leads then check the all injectors are firing, you can use a piece of garden hose up to your ear to listen.

 

Do you have Kirby Palm's book?

It's definitely a must have. Discusses the distributor seizing in detail (it's pretty much a 100% failure item until overhauled... once overhauled works great, did mine a decade ago and still works fine).

Also discusses cat failures (although mainly related to the Marelli distributors).

One further issue that *may* have caused your problem would be the cold temp sensor. Discussed on page 302.

You can get the book at:

Kirby Palm's Jaguar Resource

 

Be careful with the graphite spray. Graphite will conduct electricity and could cause misfires.

If your trunk is saturated with fuel time to remove and repair the fuel tank. There is a common failure that is discussed in "The Book".

You are positive you have Lucas ignition? Do you have 2 coil terminals in distributor cap or just 1?

If it is Lucas and you may have lost spark you want to either look at the ignition amp or the shielded wire.

 

My 1989 jaguar xjs RPM keeps going up and down. Please help