Those are the right plugs. Also try looking at rockauto.com for some parts. I believe the injector plugs are a standard Bosch 2 wire plug, nothing particularly special there.

 

just ordered abunch of parts (coolant tank, coils, plugs, plug wires, distributor cap, distributor rotor) I will probably order the plugs for the injectors shortly but I want to see if I can find them for cheaper.

I have contacted a few companies and cant seam to get a quote for a radiator recore around denver so if anyone knows a shop that would help.

anyone know what plugs are used on the coils? the wires going to my coils are pretty heavily damaged

 

Pico #518-91 (4pin connector blk/orange) for coils I think.

 

thank you, just got the coil plugs as well.

 

is the a bank ignition coil at the front or rear of the engine

 

finished all the ignition stuff. nothing looked terribly bad when I redid it and the car is running fine. However I still do notice an inconsistency in feel and sound of the exhaust on the driver side. could this be a fuel injection issue? I will probably make a new injector harness shortly but was wondering if I should broaden my search to also include the injectors themselves as a possible cause. As soon as I get that sorted out I will probably try to pass emissions again and if so the real building can begin :P

 

Yes, the injectors themselves can cause a roughness/misfire due to clogging or pray pattern problems. Every Jag I've owned has had some sort of idle weirdness. In all cases having the injectors cleaned made a difference.

I recommend:

https://www.jaguarfuelinjectorservice.com/

Cheers
DD

 

I'm on my phone so maybe I missed it but is this a marelli car?

I always found a slight unbalance in manifold vacume.and exhaust on my 89 v12, some have said
Its normal and at driving speed it all balances out. I suppose you'd know if it wasn't. Before worrying
Too much try an italian tuneup, red line it for 30mins see how it goes.

 

it is a marelli. The exhaust on one side feels very smooth so I do feel something is going on on the driver side bank. I also believe this may be causing the emission troubles so I was going to attempt to resolve it before before I tried again. I read there can be intake manifold leaks that cause weirdness on these cars so i may try just torquing that down and see if it changes anything. I would be tempted to try an italian tuneup but Im not trying to melt a piston if one of the cylinders is running lean and I probably would like to address the cooling system first as well.

 

alright I redid the fuel injector harness added a catch tank and retried emissions. it still failed with around the same numbers so im going to address fuel injectors and the fuel injector seals next.

I plan on doing this by programming a arduino to send varying frequencies of pulses to each injector and try to simulate a sweep from idle to full load. I will then compare volume of each injector to see which ones are problematic. my questions are
is there a common part number for these injectors? If I can find them cheap enough I wouldn't be opposed to just replacing all 12
Is there a good kit for seals out there and can injector seals have a impact on how the engine is running via introducing a vacuum leak?
anyone know the range of pulse durations for the injectors? If I cant find it I do have a oscilloscope I can hook up but that would be abit of a pain

 

MY 1990 XJS runs like a new car(33K miles) and all I would recommend is to do regular maintenance and make sure all fluids are top quality. Doing a drain and fill on the radiator yearly is not a big deal.... The coolant system works fine as long as it is clean and it make no sense to redesign it. I also run a bottle of Redline fuel system cleaner through it every oil change. Like others have stated for years, buy the best one you can afford and go through it and change out all fluids.I am fortunate that nothing leaks on my car, knock on wood, LOL. These beasts need to be driven and enjoyed...

 

my xjs has 130k miles and needs far more then regular maintenance I have tackled some of what it needs but still have abunch to do. but I knew that when I bought it and enjoy working on cars. My coolant system probably needs quite abit more then just a flush which is why im considering other options for it.

 

Injector clog or faulty inj. harness for one.

I will add that a jag V12 missing on a cylinder can cause sounds that are similar to mechanical issues.

 

I just did the harness and plan on doing injectors soon. the car doesn't have any noises that seem too out of place. Its really just some injector tick which I hope clears up abit when I do inj. seals.