Hello all,


I just picked up a 1986 XJ6 recently. Its BRG on tan but sat for a few years so the paint is in need of attention. Gorgeous car otherwise.

When I bought the car, it ran and drove okay, but had an exhaust leak and ran slightly rough. I had planned on doing a tune up and changing a few things to make it run better because I figured it needed to be done.

However, I had it in the garage for about a week and it will now no longer start.

Here is a list of things I have done:

--Replaced coil
--Replaced the fuel pump relay
--Spark plugs
--New gas in the tanks
--Cleaned the MAF with CRC MAF cleaner.

The fuel pump cutoff switch is in the down position and has not been activated.

The car will crank and crank and crank, but no start. No sound at the fuel pump

When I was doing a pre-purchase inspection, I noticed that there was a little silver brick next to the coil that was smoking. This was still while the car was running and driving. Is that the amplifier? It has two tan butt connections going to it.

Also, in the trunk was a box of a few misc parts. One of which was a Lucas brand "ignition control module." It was a little square with a long wire coming out of it. I am assuming that was replaced at one point. Where is that located?

I'd like to get it running before winter so I could enjoy driving it around for a bit.

Where should I go from here?

 

the brick is the Coil Ballast; Remove it. No longer used.
the ignition control module is located hanging near the distributor cap. Try replacing it with the spare.

no sound from the fuel pump? have you placed the shifter in 1st gear, turned your ear to the back seat and turned the switch to start? (cranking it), you should hear the pump charging and then stopping. Makes a sound like Saskwatch, "wooop, wooop"

 

Welcome to the forum vjz,

When you get a minute, please follow this link New Member Area - Intro a MUST - Jaguar Forums - Jaguar Enthusiasts Forum to the New Member Area - Intro a MUST section and post some information about yourself and your Series III for all the members to see.

You seem to be following a random approach to the non-start issue. Is it spark or is it fuel? Unlikely to be sudden lack of both preventing the vehicle starting. If you verify each separately it makes the troubleshooting more systematic and more effective.

Graham

 

Good news!

The fuel pump works now. So, we have a good relay and working pump.

Now, being that the new coil is a 12V, what do I need to do to eliminate the ballast? I assume somehow that needs to be connected to the leads on the coil in order for the car to fire up?

 

how did you get the pump working?

just remove the ballast entirely, send it to Doug, he collects them.

 

Just disconnect the white wires from the ballast, remove the ballast, and connect the white wires to the "+" post of the coil.....where the ballast resided a minute ago :-).

Cheers
DD

 

Thanks Doug!

I will try this today hopefully.

 

I removed the ballast and hooked the wires to the positive lead. It still has not fired up.

I looked at the fuses. They are original, and I feel that I will replace them all even though they look "fine." Now, I checked the panels under the dash where the glass fuses reside. Are there any other fuse panels I am not aware of?

The battery may also be drained from repeated attempts to start it. I'm going to throw it on my charger in the morning for a day.

If that doesn't seem to solve the problem, where should I go next?

 

Good idea to clean/check/replace fuses on general principles but there are no fuses that would cause a "no start" situation.....none that I can think of, at least.

Since the engine cranks, and you have a working fuel pump, have you checked for spark at the spark plugs? that would be the next, easiest step.

ENGINE CRANKS BUT WON'T START

Cheers
DD

 

Sigh....this car is wearing me thin.


I double checked to make sure I had the firing order correct and reset each plug cable just to make sure.

I have spark at each plug wire, and at the coil wire.

The fuel pump works, but I noticed today that when you set the car to ON, the pump runs constantly and doesn't just simply prime itself.

I'm really not sure where to go from here.

Before all this, it ran fine and then it would periodically not want to start. Now, we can't get it to turn over at all.

It has spark and fuel, so I'm not really sure what to do.

 

you said you replaced the Fuel Pump Relay; Have you double checked the connections at the Relay?

 

Good !






Someone has modified the circuit....but at least the pump runs. BTW, the "2-second prime" feature isn't found on your car. If you had a V12, it would have it





Well, you have spark and (presumably) fuel *supply*. I say presumably because a pump that runs might not actaully be delivering fuel.....and even if it delivers fuel it might not develop correct pressure.

And.....

Even if supply and pressure is good we need to determine if the injectors are working.

So.......

Do you have a fuel pressure gauge? No other way to check for correct pressure.

Do you have a test light or injector "noid" light? Lacking those, do the injectors click when the engine is cranking?

Cheers
DD

 

Now that I think of it, Doug, I don't think the injectors are ticking. I didn't hear them last night when I tried to fire it up.

I swapped the installed Ignition Amplifier box with the one from the back seat. The one I removed was oily and the one in the trunk was clean. Both were Lucas AB14 units.

I swapped it out, and it still does not start.

As far as the tools go. I don't have a fuel pressure gauge. But, I am sure some of the chain auto parts stores in town will rent one to me if available.

Where can I pick up a noid light for this car? I've never used one before.

I'm just not sure where else to go. I can't see the car developing any internal engine problems from only having driven it a total of ten miles including the test drive. All fluids are in good shape. No coolant in the oil or vise versa. Trans fluid is clean and not burned smelling.

Hmm...

 

Elsewhere in this section, in a different thread, I posted the test/check procedure for the ignition system. But, since you have spark, the system is probably OK. Look up the other thread





Good!

You're looking for 36 psi when cranking.

There's no screw-in fitting for a pressure gauge on the fuel rail. You'll have to remove the hose to the cold start injector and use taht nipple on the fuel rail for your pressure gauge


Local chain-type parts stores in my area will loan/rent a set like this:

OEM/6 pcs. noid light set (27161) | Injector Signal Tester | AutoZone.com

Or you can buy the individual correct noid light for $5-$8 on-line or at some of the better auto parts stores. You want "Bosch type" or "Older Bosh type"....something like that.

The light just clips into the individual injector plugs. If it blinks when cranking the engine, the injector ciruit is at least fundamentally operational. In other words, it'll identify if the circuit is "dead" or "not dead".

It won't identify a defective injector, though. But, those failures are rather rare



A spontaneous internal engine problem is unlikely, yes.

Just gotta go thru the trouble shooting steps but, yeah, you need a few tools to do so properly.

Cheers
DD

 

On this system the pump runs continuously when the engine is running, and excess fuel supply is returned to the supply tank via the pressure regulator, and return lines and valves. However the pump should only start to run on engine crank and start, not just with the ignition turned on, so somebody has fiddled with the system before you arrived !

Have a read of these internet webpages as it tells you how the assembly is designed to work. Remember one thing is absolute key - no ignition pulse at the coil = no fuel injection pulse at the injectors. The whole L-Jetronic shebang depends on the ignition pulse. so if it is not getting through to the ECU then the injectors will not fire. Earths (US=grounds) are also key in getting it to work, so make sure all engine loom grounds are checked out, plus break and remake connections to restore connectivity. You should be able to hear the injectors firing, (audible clicks), as they all fire together twice per engine revolution.

Fuel injection and the Jaguar XJ6 4.2 Series 3 / AJ6 Engineering

From what you have told us, the car really should be starting. Have you timed the engine 180 degrees out ? Also Jaguar number the cylinders from the transmission end of the engine.

Its difficult as I'm at least 3000 miles away, so cannot pop round and help, but you would seem to be close to getting a start. Other thing might be lack of compression due to standing, so a bit of engine oil in each cylinder, plus a good crank without ignition might bring it back up.

 

A couple of quick and dirty tigs to get it going. Might work.

Jump 12v battery to the + post on the coil. Crank the engine, there is a fair chance that it will fire.

Tap each injector a little whack with the back end of a screwdriver. It either shakes the piston into moving or dislodges a grain or so or rust.

And, as to the amplfier. Could t be that the drty one works and the clean one does not?

There is a way to bench test them. Google "bench test GM ignition module".

I lost the process in a PC crash!!

Carl

 

Thanks guys.

I may try that about tapping on the injectors tonight. It is certainly worth a shot.

I replaced that ignition module with a new Delco unit. It was $50. It still has not started. So, I think I am ready to rule that amplifier/ignition module out as a possible cause, or no?

I'll still need to purchase the noid light kit and fuel pressure gauge. Advance Auto Parts in my town has both, but unfortunately you can't rent either of them.

That's a matter for tackling later in the week (university mid-term exams).

It would certainly be nice to get this thing running before it needs to go into storage for the winter.

 

I hope you got the right Delco module, and I am sorry if I steered you to replacing a part that did not resolve the issue, but looking at the bright side, you now have a new module that should give long service.

this is very puzzling.

 

Yeah, I'd say so....especially since you previously reported that you DO have spark. If you have spark it's pretty hard for the module to be faulty.

Cheers
DD

 

Jose,

We got the Delco one through the local parts store, so I am assuming that it is correct. The numbers matched up.

I am going to pop off the cold start valve and see about the fuel situation there here in a little bit.