Can we figure out why this Jaguar V12 won't run? Diagnosis Steps - 1989 Jaguar XJS

The second part of our intro series for the 1989 Jaguar XJS, we look to see if we can figure out why this V12 won't run. Included are lots of details regarding steps to troubleshoot the ignition system, as well as some tips on how differences in the various Lucas systems may affect your tests. This does not cover much on the Marelli system.
Stay tuned and subscribe for more - in the next installment, we'll replace some parts and see if this car will run!

[@ericcooper5867]

This video is an absolute godsend haha, there's very little information about the lucas ignition system on KZbin so thanks for that. But ill probably be switching to the mobek independent system as it is basically modern reliable ignition and fueling without all the vacuum operated nonsense

[@frankmgallo]

Great info keep it on the road

[@Schlipperschlopper]

You cant use V12 Jaguars because they all drop valve seats after a while!

[@crasbee]

2:20 "And I know with the age of this [the spark amplifier], I wanna rebuild it regardless of anything else." - While I do understand what you're saying here, this approach has severely bitten me just a couple of weeks ago. The Volvo of my partner was misfiring, so he diagnosed that it was one of the ignition coils (by swapping two and seeing if the misfire goes to the other cylinder as well). I recommended to replace the gasket under the VVT solenoid, which has a little screen that often dirty. He cleaned the VVT solenoid as well and replaced the ignition coil and when the car was started, it ran absolutely terrible and wasn't really able to hold idle. But now we had a problem: We possibly introduced another problem to the one we already had! In the end nothing was faulty, but the car just had really unfortunate adaptation values stored in the ECU. We unhooked the battery for 10 minutes and afterwards the car ran and idled fine. But we learned: Don't introduce new variables, because then you don't know what to look for 😅😅

[@hardit359]

My 1984 V12 has the one coil as per your video, but also another one mounted in front of the radiator away from all the heat inside the V of the engine

[@VortexGarage]

This one still had that second coil also in front of the radiator. From what I can tell it was decomissioned and wiring disconnected, with the single coil in use. That appears to be a fairly common "upgrade" - a modern more potent coil that can replace the dual coil setup. Time will tell if it's as reliable though!

[@Andre-ln6lx]

I wonder if you had similar issue I did re replacement pick up coil and link lead. The new pick up replacements seem to be wired incorrectly - compare old wiring to new before installation.

[@crasbee]

16:27 The rading is MOhm, which is Megaohms, not Milliohms (mOhm) :) But I'm sure it was just a slip of the tongue.

[@VortexGarage]

Yes indeed! I also didn't catch and note it, so great catch!

[@YouknowmeOUdo]

I cannot find the rebuild video of the AB-14 please direct me to it, thank you!

[@VortexGarage]

Here you go: kzbin.info/www/bejne/eKPIc6SPiKd1p9U