Jamie, I would be also interested in buying one of your fuel injection harnesses, don't know if anything would be different on an '89 Marelli Ignition XJS.

 

I'm afraid I recently changed jobs and no longer have spare time to build one, or even work on my own car!

The job is pretty simple, just time consuming. I think the best method is to take your old harness out, label each plug and strip off the loom covering. Then build your own using the original as a pattern. I made mine slightly longer so I could move the wires up and out of the valley.

 

Has anyone on this thread identified a good US source for the bosch plugs, high temp wire, and sheaths required to take on this project. The only sources I'm finding require the purchase of long lengths of cable. This will soon add up to a lot of wasted money.

Any pointers appreciated.

 

My 90 XJS has 32K miles and the harness and hoses still look in really good shape. How many total miles on your V12 XJS cars before having to replace these items? 80K miles, 100K miles? Thanks.

 

Mine has about 85k and is crispy. I recently had a Marelli failure which I attribute to stress caused by misfires arcing out the rotor.

Plan to replace it this summer.

 

I built my own recently. I bought some wire from this ebay seller;

brussellex | eBay

I couldn't any high temp harness in Japan, so I had to buy from abroad...

I think the cheapest EV1 connector will be this;

BMW E30 Bosch Fuel Injector Connector M3 M5 318 325 EFI EV1 | eBay

What is to be aware of is the later style EV1 connectors with a quick release spring won't fit to pre facelift XJSs without modification.


In the end it cost me like $100...
The wires were like $35, the 12 connectors about $40, 6pin male & female connector $8 each (of course you can use cheaper ones but I bought good waterproof ones)

 

My 1989 has 78.000 miles on the clock and the entire wiring loom for the injectors (and the plugs) are looking worse and worse as the day goes on. I'll be making my own harness soon... Just need to find time!

 

Daim, I really liked the photos you posted in your fuel line post. I noticed so many differences between the 5.3 liter and the 6.0, that I really hadn't seen before. Do you have any photos of what your harness looks like?
Danke,
Bill

 

Hi Bill,

when I get around to removing and rebuilding it, I'll have loads of pictures

If you were wondering, if the 5.3l is the same as the 6.0l, have a look here: v12s - Official Website

According to that, my harness would be the same as until end of 1990 (VIN 17846).

But as said, I'll do a proper "how to" when I get my harness ready Might take a few weeks/months though!

 

Thanks Daim, yes I'd be interested in seeing what an original harness looks like on the 5.3.
If I read some of the previous posts correctly, then it seems like on the 5.3, the harness enters the "V" from the front of the engine. On mine, it enters from the back. I'm also curious as to whether the ribbed shield on mine is also standard on the 5.3's.
I've attached a not too great a photo which shows what mine looks like.

Bill

 

If I remember correctly, the harness enters the V section from behind (at least as far as I have seen). I've got the front end of mine basically in pieces and there aren't many wires/cables in the front there. Most wires are lead in from the rear (as far as I can tell).

Just a question after seeing yours, you have the Marelli ignition. Does the front coil pack sit there properly or is it, like on the '89.5 fitted above the other pack?

 

Hi Bill, the harness of the facelift model also comes from the front, but it is tied with the harness from the back(RH for the engine management and LH for the air conditioning) with harness tape.
When you cut the tape and disassemble the harness you will see what it is like.

The second pic shows the injector harness connector.

 

I've got to correct myself. Yes the harness does enter from the front... Which isn't a bad idea... My older Volvos all have it enter from behind and the cables tend to snap then...

 

Thanks Daim,

Yes, I have not touched either of the coils. They are still where I found them!
This might be a better picture.
And that's the harness for the left bank (looking forward from inside the car) on top of the "A" coil and on the distributor.

Bill

 

Thanks Japthug,
I'll be the first to admit that I am a novice at this automotive DIY stuff but, I'm fairly certain that it's not a Facelift/Pre-facelift issue. I believe it's a 5.3/6.0 difference. There is nothing coming in from the front of the engine. As you say, there are other wires included in the harness (A/C, and another I didn't recognize) but the entire bundle starts out inside the right wing, goes to the firewall, and enters from the back of the engine.
If I were home, I'd try and get a better photo, but the one I posted just above here is the only other one I've got.
One of the things I'm trying to figure out is, is that ribbed shielding only common on the 6.0's or were they also original for the 5.3's?

Bill

 

As said, I've found my injector harness come from the front (it is clipped to the top right radiator hose).

While I'm at it, is anyone interested in a new injector harness? I might make a couple more than I need (haha... One is enough for me! )...

 

Btw.: my V12 has cotton/fibre coating rather than that plastic piping...

 

I replaced my wiring harness earlier this year, it is not a difficult thing to do, it may sound complex but when you start its quite easy, I refer you to this thread that has further information https://www.jaguarforums.com/forum/x...st-pt2-113163/ post2 and FI Harness Rebuild
Sorry I have not read the complete thread and if I have repeated something so be it.

 

Hi Bill,

I am sorry, you are right, the 6.0 injector harness comes from the behind, according to the the electrical guide the connector is in the right inner fender.
It must be easy to access to it, when you remove the backside cover of the wheel housing you will find it.

The engine cover is unique to the 6.0s.
My facelift 5.3 doesn't have one.

 

Just ordered myself 12 injector plugs. Hope they arrive by end of the week. At the same time, the wires are ordered too...

I'll see how this goes...