Dear helpful forum, my green monster decided to develop some issues in the engine wiring harness. Seems like after all the years the wiring strands and also the insulation of some wires is starting to brittle and partly break apart. It all started with the injector 7 suddenly going on strike. While looking for the fault in the wiring several other cables also seem to have fallen apart.
The ECU I had checked at an electronics company (not easy to find) who said that everything they can test about it without being in the car is ok. All amplifiers/outputs of the injector circuits measure ok. So all injector circuits seem to be generally not defect.

I was then lucky to find a used and well preserved engine wiring harness in the classifieds and we thought to change it in.

But my indy workshop, usually really good and always ready to boldly go for it, start to shy away from the seemingly massive amount of work. Does anyone here have experience with this sort of surgery on an early 4.2 na model? Or has touched enough different places in the engine bay already to have an idea of the magnitude of a harness change?

Last report by the workshop is that they have to disassemble the AC compressor and complete accessory drive to fit the harness. They now also said that in order to take out the AC compressor it was necessary to take out the front axle.
If that is really true I would seriously question my love for the car and weight it carefully against my wallet, and chances are good the wallet would win.

Anyone here who can give a qualified estimate on how big of a task the change is, what parts have to be disassembled out of the way and what it really means to get these out of the way of a new harness?
Would really appreciate any comment on this task.

Cheers from a (still?) enthusiastic Jaguar lover

 

New fuel injector connectors, with the wires attached, are available at Rock Auto.
As well as other places on the computer.
Way easier, & cheaper to replace, than the entire wiring harness, I M H O.

 

I can't answer for the air conditioning compressor, but I've worked a number of the connectors on top of the engine during my cooling system overhaul (linked in my sig.) From that, I know of two connectors at the rear of the engine which require removal of the intake manifold to access. You don't actually have to take it out of the car (unless you're going to replace the valley coolant hose or the knock sensors,) but it has to be lifted and pushed forward so you can reach the MAP sensor connector on the back, and the fuel temperature sensor at the rear of the right-side fuel rail. You can touch but not disconnect that fuel temperature sensor connector with the manifold in place, but you can't get close to the map sensor connector while it's on the engine.

 

Regarding the A/C compressor, I have had a look at the workshop manual.

According to it, the front axle does not need to be removed, but the steering rack needs to be, albeit without detaching any tubes.

It is still a biggish job, as the engine needs to be raised to remove the engine mounting and to be able to access the compressor bolts.

Best regards,

Thomas



corrections

 

Thanks for the estimations. So it seems my workshop hasn't exaggerated with what the need to disassemble for the change ... too bad .
I think I'll settle for a rework of the injection part of the harness in place. That is still a lot of fumbling (especially also to then splice the LPG system back into the new wires) but still better than ripping apart half the engine bay and front axle.

I wish I had a supercharged one, they have a separate injection harness part 😁

I should never have settled for a car that I like as much as this Jag. All others before were much easier to just dispose of when the became annoying 🥲

 

Good choice, I M H O.
One hesitates to mention the word addiction in relation to these cars.
Is Cat Scratch Fever a nicer term?
What ever one calls it, there are two residing in my heated garage.
Along with three motorcycles, & the necessary shop equipment.
To accompany another of my addictions.
Fortunally many are able do double duty.

 

I think it is absolutely justified to call it addiction.
It is my first car in 35 driving years that doesn't make me want to drive it as fast as it can go. "Soothing" may be a good term for it.
Fortunately on 2 wheels I had found the same effect already years ago with my BMW 2V flat twin GS, otherwise I might not be around anymore, if I had kept sticking to maniac Japanese 4-cylinders 😎

So harness repair it will be, but that will have to be timed for February

 

Unaware just how fast either of mine will go.
But tripple didget numbers happen with no real effort.
As for two wheels my two 84 GL1200 standards, are the same.
Suposed to have a top end of about 160, have seen 130 years ago.
One runs out of straight empty road, too fast over here

 

We still have some open stretches of Autobahn where it could be tried. Officially it is limited to 250km/h, but I only once saw the 2 in front shortly.
Just too much hectic for a car like that (not to mention the 20+ year old suspension, which wasn't even really built for that when it was still young and fresh).
Such a Victorian-style living room atmosphere is made for floating, not racing. Much more difficult now in my BMW winter-car to keep the same calm attitude towards the road 😁

 

I like to drive fast, if the traffic and weather conditions are suitable (and there no speed limits, of course...), so my Super V8 gets to see the "2"quite often.
At the same time, it is just so relaxing while driving fast, even if this sounds as a contradiction... it is a fact that I reach destinations much more relaxed in the Jag than in one of my other cars, the Jag being the newest and most powerful I own.

I do not concur with the statement that the suspension was not built for that, but then I have replaced everything during the last 6 years, including the Bilsteins, so it is not that worn. I feel perfectly safe when travelling at high speeds, even on routes like the "Kasseler Berge"...Germans know the highway I am talking about.

Best regards,

Thomas

 

Thomas, you may be right abut the age-state of my suspension 😊
I'm quite sure that most is still from 2003, except the rear suspension bushings that I changed approximately 6 years ago.
But as my usual life with it takes place around 160 to sometimes 180 I'm fine with that.

 

I understand. I bought the Jag because I was fed up with not having any reserves when the speedometer hits the "2", and as am a lazy person that does not want to do jobs twice :-) , when I had to replace some parts of the suspension I just did the whole thing. The Bilsteins had to be done because first I had a front one leaking a bit of oil, so I replaced both fronts, and then a few years ago one the rear ones blew...that's a sound that I do not want to hear again! So that meant repalcing the rear ones.
Fortunately, the Bilsteins are quite readily available here in Germany.

Best regards,

Thomas