My 88 XJS V-12 engine has an issue. Last weekend I started my normal engine warm-up and let it run at idle for about 20 minutes and then died. It's always been reliable on startup, though depending on how long between driving it may take a shot of starting fluid to get it started. I keep the tank pretty full of fuel at all times. The engine ran at idle and then quit. During a couple of re-start attempts it never even tried to fire off, even with starting fluid.. Its as if there is no ignition, though I havent yet checked for spark at one of the spark plugs. I considered that there may be a tank fuel pressure issue because in past I have heard vacuum suck when I open the fuel tank to refuel but when I opened the fuel cap this time there was no sound of released vacuum. I Anyone here have any ideas?. .

 

Hi 51 rover

If you have to keep using Starting Fluid, something sounds radically wrong as really one of the only times that you use that Stuff, is to test to see if you either have an Ignition type problem, like for instance checking for a Spark, and to see if the engine is getting fuel, as its almost unheard of to use it on a a regular basis when you start your Car if She won't fire up

And also instead of a 20 minute Warm up, its best to get her out on the road as soon as you possibly can and then let her Warm up at a Sensible Speed, as most of us are known to do on here

As you have an 88 could you please confirm you have a Lucas, as opposed to a Marelli ignition Car, as the Fix could be a little bit different

Like for Instance the Crank Position Sensor which the Lucas Car doesn't have

Though even so the list could be a long one, you could make a start by removing a Plug and seeing if you have a Spark

 

51rover,

As OB has intimated, there are a variety of potential things. It's important to do your analysis in a very basic and structured fashion.

Don't change any items yet, even if you think it;s a good idea. Start with absolute basics - Pull a spark plug, and pull and injector and place in a jar. Confirm you absolutely have sparks firing and injectors spraying effectively whilst the engine is cranking. Until you can confirm that, I wouldn't start doing anything else just yet.

Good luck

Paul

 

My 88 has the Marelli ignition system in it. I may have been unclear on this but I normally do not have to use starting fluid to start it unless it doesn't start within a rather short time of cranking on the battery. I don't drive my car much during winter so it may sit for as long as 3 or 4 weeks before its next excursion. Mileage on my car is about 95k. I think what threw me off was that it has never shut itself down since I've owned it. When I start it periodically it is always to take it out for a drive. But this time it was just to get the engine warm and then shut it down because the last time I drove it the throttle linkage rod cables got stuck on full throttle and nearly killed me. It seams the plastic/rubber rod bushings were half gone. I ordered new ones and have them to put in but not done so yet. Looking at the bushings and how they get stuffed into a smaller hole makes me think there is a trick to get them installed that I'm not aware of yet, but thats the reason I'm not driving the car yet and just warming up the engine. Soooo, now the engine can't be warmed up till I do some checking!!!

 

Hi 51 Rover

It sounds like a fairly easy Fix but can you get some photos, so we can see exactly what you mean, though you could make a Start by Cleaning the inside of the Throttle Bodies, which is going to need to be done before fitting any new parts (Photos of any New Parts would also help)

Just a Side Note for anyone else:

Do this with the Engine OFF! as the Suction is so Great that it could ruin your Engine if a Cleaning Rag got Sucked Inside

 

Update to my problem. Last night I decided to try starting it again. Sure enough, the old girl started right up. BUT, it blew smoke out the exhaust like I've never seen before. It has never done that. The engine idled rough, like in might have been running on half the cylinders. I reved it up a little bit and the roughness shook the engine so I cut it off for further checking. Any more ideas are appreciated.

 

As this a Marelli car, it could be the famous spark failure on one entire bank.

 

Hi 51rover

Got to agree with 'Greg' on that, as this sounds like the prelude to a Marelli Fire, where one Bank of Cylinders has completely shut down which means Raw Fuel is still being Pumped into the Exhaust/Muffler on the side of the shutdown Bank that holds about a Gallon of fuel and if that suddenly ignites, then you could very easily have your Car Catch on Fire

So first thing to do is take the Cap off the Distro and check around for any signs of Burning on the Rotor and the Cap and then report back with your findings and also don't attempt to drive your Car until it has been fixed

 

Wow, that sounds exactly like what's happening. I never would have guessed it. I'll check it all out in the next couple of warm days (big cold front coming in tonight) and won't drive it until I've got answers. The description you're giving me answers why the engine exhaust roaring out blue smoke smelled so bad, not like normal exhaust and had a kind of burnt smell. I hope nothing serious got damaged in the process.

On a similar note, since I had the throttle cable bushings fail making the linkage sloppy enough cause full RPM lockup, I think I'll replace those rubber bushings while I"m checking things out. Does anyone here know an easy way to push in the new bushings? I was thinking that maybe you heat the new bushings up in hot water and then push them it. Anyone have a more efficient way to do it?

Thanks for everyone's input on solving this issue. . .

 

Marelli cars have two coils as well, you might have either bad connection or a failed coil on on bank.

 

Hi 51rover

That Bad Smell you are getting could be the 'Cat/Cats' melting, as if you were close to having a Marelli Fire then it's not unusual for the 'Cat or Cats' to Glow 'Cherry Red' and so you could find your Exhaust is blocked off as well

As for the Coils, the Lower Red one feeds 'A' Bank and the Upper Yellow one feeds 'B' Bank

Underneath the Distro Cap you have what they call a Stepped Rotor, where the Upper part Fires 'A' Bank and the Lower part Fires 'B' Bank as the V12 Engine is like 2 X 6cyl Engines joined together and its almost always 'A' Bank that Fails First

So don't be surprised that when you take off the Distributor Cap, that it looks like an Electrical Arc has been trying to burn through

Marelli Failure is most often caused by poor maintenance. where for instance the Spark Plugs underneath the Air Con Motor have not been changed since they are such a PIA to get to

Hope this helps even if it doesn't seem to make you feel any better

But at least your Car is still in one piece and so that is something to be grateful for

Alex

 

Further edit and update on the engine failure. I was wrong about the ignition being the Marcelli system. Despite the cold weather this weekend I did a visual under the hood to take some pix. My system has the Lucas ignition. I now know there is spark to the spark plugs. Because it will start but run rough as hell it looks like the next step is still to check out the distributor cap and rotor. The secondary ignition wires are all new, replaced last year, maybe 1000 miles on them now. Dang, after looking at the distributor yesterday I had forgotten what a pain it was to remove the plumbing and wiring just to get the the rotor and cap off!!

 

What sort of shape is your injector loom in? Your symtoms, being a Lucas car, can be caused by injector an injector loom short to earth keeping the injectors open.

 

I would be surprised at Marelli in 1988, but who knows, clearly sorted now.

Remove the condensor thing from INSIDE the Ign Amp, well documented, and in my sticky at the top of this section.

Injector loom, YEP, old age, it is a mongrel.

When it does its stupid thing, you need to identify loss of:
Spark
Injector pulse
Fuel AT the rail.

NOT easy on the side of the road, but doable.

How old are the spark plugs, HT leads,.

Another thing to check,:
The WHITE wire on the main coil has 12V when things go AWOL, RARE, but ya gotta know.