this vehicle has been standing for some years
it had a small engine fire, burnt some wires at the back of the motor.
i got a leci to fix the wiring, he said definitely not an electrical fire ( i thought the same)
Tried to start it, no luck
Cracked a fuel line to the fuel rail, got pressureFitted an impulse globe in one of the injector lines, got a flash when turned on the ignition, cant get anything sinceHave got 12v to both pins on the plug with the ignition on but nothing when cranking or no flash when I first turn the ignition on
Give it some aerostart and it idled for a few seconds.The oil light was on at first but now the oil light doesn’t come on at all.
1988 V12

 

Hi knares

Down by the Front Headlight Nacelle (Drivers Side on a UK Car) is a Silver Box with a Plug going into it (The Resistor Pack)

If the Plug and Socket are dirty or Corroded then this can play Havoc with the Firing of the Injectors and is often overlooked on an XJS that won't Start

Its a bit awkward to get to but its only held on by one or two small bolts and needs to come out to be cleaned because its facing upside down

The Pic is the Resistor Pack on my Car with Marelli but your Lucas Car will have one that looks almost the same



Resistor Pack on an XJS needs to be this Clean



The Plug that goes into the Resistor Pack needs to be Clean as well

 

Shielded wire from the Ign amp (top of LH inlet manifold) and terminating AT Pin #18 of the ECU is not providing an ignition pulse TO that ECU, so it has no idea there is an attempt to start being made.

Many threads about this form me and others.

If in doubt, PM me your phone # (NOT in here as this open to the WWW and scammers) and I will talk you through it.

Not hard to sort in any way.

 

OB thanks for your replyI did read your post in another similar thread, I did remove the plug, it looked ok, I gave it a spray with CRC anyway, I think that part is ok thanks

 

Grant Francis thanks for the info, you make it sound so easy, makes me feel confident. i did read your comments in another post as i have been searching for advice.
I haven’t tried to do what you have said, that was my next move, i have to find the ECU first, i believe it is in the boot.
quite possible now i think of it, that might be one of the wires that got burnt, as i think that wire goes behind and on top of the engine.The leci who fixed the wires is very good but we couldn’t start the engine so he wouldn’t know.Thanks for your offer, will have to get it ready first

thanks

 

OK, 100% got burnt.

It is a tad fickle to find, and opening the loom at the rear of the engine all the way to the booster area is the best way to do this properly.

Standard TV antenna coax is just fine for the repair. By the metre at JayCar etc.

 

hi
is this the wire
the weather is not good today but i did get the photo
thanks

 

That's it !


Cheers
DD

 

first of all, thanks fellas for your input
Great success to day.

I cut the cover off the wire at the end, exposing the braded sheath, I put a ohms meter between the sheath and the center wire and got a reading, not a fully closed circuit, but some leakage.
I cut back the cover some more, about a foot, past where the fire was and found the braded wire had suffered from the fire.
.I cut the damaged part out and put the ohms meter on it and got a similar reading.
.I put the ohms meter on the sheath and the center wire which goes to the boot and there was no leakage.
As suggested in a previous post, I connected some antenna cable to the original cable.
When this was done, I tested it again and there was no leakage.
I joined the black wire to the sheath, but when I tested it I had leakage.
I removed the black wire, there was no leakage.

I had a noid light on one of the injector connectors.
I turned the ignition on but there was no flash from the noid light I tried it three or four times, nothing.
I thought I would crank it, as soon as I touched the key it fired and the light flashed..
That was the easiest it firedWhen cranking it, it will fire and run very badly for a few seconds and sometimes up to about 1000/1200 revs, then it just dies.
There are no bad noises, I think.
The car has been stood for a number of years (3 or 4) so I was told and the guy across the road says the fuel smells off, but if that was the case, I would have thought it wouldn’t have fire at all.
So, the question is, should I connect the black wire, should there be leakage there.
I know I should have tried it but I ran out of day light.

I put a ohms meter between the sheath and the center wire and got a reading, not a fully closed circuit, but some leakage
I cut back the cover some more, about a foot, past where the fire was and found the braded wire had suffered from the fire.
I cut the damaged part out and put the ohms meter on it and got a similar reading.I put the ohms meter on the sheath and the center wire which goes to the boot and there was no leakage
As suggested in a previous post, I connected some antenna cable to the original cable.
When this was done, I tested it again and there was no leakage
I joined the black wire to the sheath, but when I tested it I had leakage
I removed the black wire, there was no leakage

I had a noid light on one of the injector connectorsI turned the ignition on but there was no flash from the noid light
I tried it three or four times, nothing
I thought I would crank it, as soon as I touched the key it fired and the light flashed.
That was the easiest it fired
When cranking it, it will fire and run very badly for a few seconds and sometimes up to about 1000/1200 revs, then it just dies
There are no bad noises, I think
The car has been stood for a number of years (3 or 4) so I was told and the guy across the road says the fuel smells off, but if that was the case, I would have thought it wouldn’t have fire at all
So, the question is, should I connect the black wire, should there be leakage there
I know I should have tried it but I ran out of day light

 

Trying to work out the best and easiest way to drain the fuel

 

The reason you are getting a reading on the wire with the sheath connected is because you are measuring through either the ECU or ignition amp to ground, this is normal.

I would measure the centre conductor of that wire with an ohmmeter front to rear (NOT centre to sheath), you should have less than 1ohm, more than this can cause issues with the pulse the ECU sees. Depending on how you joined the coax this may cause you an issue.

Other than that check dissy is correct and rotor is lined up with 1A at TDC compression stroke. Plug wiring etc.

 

Hi Knares

Your Car isn't showing up in your Signature but I seem to remember reading that you have a 1988 V12

One of the ways to drain the Fuel and quite possibly the Best way, is to look underneath the Car about where the Battery Holder would be in the Boot/Trunk

Where you should see a round rubber Blanking Grommet

Hook that out with a Screwdriver and then as you look up the hole, you should see what looks like a Nut with a Spout sticking out

Find a length of Polythene tube to fit over this, then temporarily remove it while you loosen that Nut (which is a Tap) with a Socket

Then put the Polythene Tube back and then undo that Nut a little bit more, at which point Petrol will flow out, which you can then collect in a can to dispose of



Fuel Drain Tap under Car of my XJS V12

Once the Tank is empty you can then 'drift' the locking ring off the Sump Tank with a Rubber Hammer and a Piece of Wood (so you don't get any Sparks!)

Clean it out and then Replace the Internal Filter



Another View Showing position of the Blanking Grommet in relation to the Muffler/Exhaust



The Sump Tank in an XJS V12 this is what you are draining when you undo that Tap underneath which is then refilled by Gravity from the Main Fuel Tank

Don't go pulling off Pipes in the Boot/Trunk as its all fed by Gravity and you would almost certainly have Petrol flowing everywhere in the Boot/Trunk

Disconnect the Battery First and do this Job Outside

Normal Safety Precautions: Fire Extinguisher Watch out for Fumes and beware of any Sparks

And also change the Main Filter: After you've drained the Tank

 

"Like" x 10 OB! Where is the like button on this forum. I didn't know about that drain! Go figure. I had to drain with the fuel pump and extended hose. Fire extinguisher handy. I didn't enjoy that at all. All I could think about were sparks. Learn something new every time I'm here!

Drain that gas, gas gas gas! Then, for cheap money, I got a whole new length of shielded wire from eBay. What I was told was that the wire is shielded because any electrical interference can and will throw off what the ecu understands and a splice, home fix and retape/recover will just not due. The coax is surrounded by other wires. Rerun it. Thankfully I didn't end up having to do mine. Problem was what I will describe next.

Another thing I found, it appears I also had a small fire (PO), was that there is a small hose coming off the back of the balance pipe (the 1inch or so pipe that crosses the back of the motor - around where our fires were) that talks to the computer ECU for fueling... Then a skinny orange one (on an 88 maybe not) that talks to the ignition computer (maybe just marelli ignition????) that might have melted, too. Both important vacuum lines. Somehow, mine fired up the other day when I was working on my OPress sensor back there and had removed the hose and forgot it. If I hit the gas it would stall, it wouldn't idle long or right, then wouldn't start at all. I reconnected the hose on the balance pipe, and back to normal.

I also have to get to that back of engine loom and in inspect inspect. Hoping to pull everything around it to get to the electrics properly. I am sure (i know) I have missed some things. I am looking very forward to spending a few days with a soldering gun and straightening out and tidying up wires in the engine bay.

love this forum.

 

Yes, Jay, this is the second time I was reluctant to ask a silly question and was real glad I did.I was going t do it like you did

 

Hey Brother -

1. these are jaguars, so in that, there is no such thing as a silly question, lol.

and 2. these are OLDER jaguars, there is no such thing as a silly question.

Let me tell you about my problem removing the GD steering wheel, lol.

In both cases - the silly question is the one that is not asked. Not much is 'automatic' these critters. We are all learning here, from what I can gather.

I have worked on cars, machines, houses, appliances and 'things' all my life - and I have to say there is something unique about Jaguar language and the way things come together - and they do. The folks here are amazing!.

which is all REALLY cool, if you ask me!

 

Hi Jay

Nothing to do with me Bro, I just pick up the Spanners and do what 'Greg' and 'Grant' tell me, or 'Cherry 'B' would still be broken down and in the Garage

 

i rang the jag people today, spare parts
i thought as the Shielded wire from the Ign amp was often a problem, they just might sell it separately.
didnt know what i was talking about

 

That's one of the problems with these Cars, as its getting more difficult to find some of these Parts, which often means that sometimes we have to improvise

Did you try the TV Coax that 'Grant' suggested

 

i did as Grant suggested with the TV coax and it did start in a fashion but i thought if the cable was available i would replace it

 

Hi knares

Think yourself lucky its only a Wire, I could do with a new brake pump but they are NLA as are lots of other essential spares like that