Hey fellas-

Ok, so, no water in the fuel. Its also -7 here. Water freezes. The weak spark is across all of the coils not just one. With the cold weather I am very careful with the packs themselves, the clips and the wiring.

@1geo1- Would you read over that very first message I posted for me and tell me what you think. For me I feel like its an electrical problem through and through. I took off the intake to check it for cracks. No issues there. I feel like even with a crack it would still run... just badly. I've had consistent fuel pressure the entire time. Enough gas to smell it at the back of the car. woof.

As far as your seat problem goes. Its pretty easy to get to that fuel tank. Once you take the carpet in the trunk out the tank and lines are all exposed. Its just a couple straps and you can get the whole tank out with it still in the trunk if you wanted too...?

This video is pretty good...
I have a service manual, I could dig around in there if you still think removing the rear seat is the best way to go. Let me know.

Thanks,

-Mitch

 

1geo1- you are highjacking this thread and turning it into a pump replacement thread. It would be better to start a new thread.

As to replacing the pump without moving the tank, you will have to go through the parcel shelf. There was a thread in the X300 forum on that subject, so try a search there.

 

Does anyone have a direction to think in?

I have fuel air and spark... still wont fire. What can it be? *SPARK IS WEAK*

I have compression, do not say bore wash.

Where should I look???

 

I keep opening this thread hoping to see some good news. Most baffling issue I have seen on this forum.

A thought: sometimes you need to bite the bullet and tow it to the dealer; for your blood pressure, if no other reason.

Maybe the temperature sensor (at the crossover pipe). Might also try some starting fluid down the throttle bore just to see if it wants to kick over.

You might also need to have the ECU reflashed.

The tensioners were replaced, right?

 

Thanks for the compassion Jhartz. I appreciate it.

My major clues are:

Sudden death after thaw
No issues prior to the event
apparent weak spark
No fault codes

I feel like its a low voltage, electrical malfunction...

Oh those Jaguars! *laughs and cries

 

So, you still have the original tensioners, right?

You haven't taken it to a pro, right?

And, now new news started after what "thaw?" The car is in a heated garage so we can rule out ice, right?

You have measured the voltage at the connector under the hood, yes?

Ain't compassion but analytical drive . . .

 

Allright now we cookin...

Haven't taken it to a pro.

In my first post I talked about how I took it to the shop for an inspection and tires. I dropped off the keys they brought into their heated workspace, left it running let some of the ice drip off _then_ it stalled when they were pulling it into their bay.

I'm not sure what you mean about connector under the hood... there are hundreds. Please elaborate.

 

Check the power supply to the coils. The ECU grounds each coil lead to fire. All coils receive a common 12 volt supply. A relay supplies the voltage. So, if your guess is correct, you are looking for a low voltage supply to the coils.

 

This is a mystery worthy of Agatha Christie. It's hard to believe something would just fail at the inspection station. How about the ignition relay for the coils ? Maybe something to do with water dripping ?

 

I checked every relay and their terminals for voltage.

Anyone know of a steadfast way to check engine timing? If the computer says everything is fine and I have no fault codes I feel like I should look there. But I would like to check the timing without tearing the front of the car off?

Keep in mind I'm in Utica and the weather sucks ***.

Thanks,

-M

 

I used a straight edge across the intake and exhaust cam flats. You can find it in any of the instructions for replacing the secondary tensioners using the tie method.

This also allows you to check on the condition of your plastic tensioners.

But if you're convinced that the problem is not broken dentures. (For cwist sake Siwi, what's wong with you?) TENSIONERS, then try starter fluid in the throttle body.

I think, but I am not sure, a bad sensor would have set a code. But maybe a pro might comment.

I still think there there might an icing problem that caused the initial stall and failure to start back up (although the wet plugs may rule that out, minus seven degrees may have an impact on your problem).

 

I dig what you're saying. I appreciate the sentiment but, I don't want to take it anywhere.

Back to the timing possibility. I watched a ton of videos today regarding swapping the chains, tensioners and other bits. What I was asking was is there any non-invasive way to test the timing?

By your description it looked like you were talking about changing the chains..? Maybe I'm missing something.

Thanks,

-M

 

A direct answer to your question, NO! I know of no one reporting a non invasive timing check that is practical.
You could (theoretically) use a two channel scope to compare the cam sensor pulse with the crank sensor pulse, but you would need a sample car to compare with, since I doubt there is a spec readily available as to the time offset.

Removing valve covers is pretty non invasive in the grand scheme of things.

 

Hi m1eckler,

I've been following your thread and am sorry to hear you haven't uncovered the issue yet.

At this point I guess I can't do any harm by offering the following random thoughts/questions:

Your weak spark seems like an obvious issue. What voltage to you measure at each coil electrical connetor with the ignition switch set to Position II (ignition ON but not cranking the engine)? The power arrives from the ignition coil relay on the Purple/White wires. You should have a good strong minimum 12V. If not, check the relay again (in the engine compartment control module enclosure) and the EMS relay (in the engine management fuse box).

The common ground for the coils are on the black wires, which splice together and then pass through the black 57-way connector on the bulkhead behind the engine, then on to the EMS LH ground stud, which is on the left side inner fender.

The Green/* and Slate/* wires for each coil connect directly to the ECM, with the Green/* wires connecting independently and the Slate/* wires splicing into two groups of four that connect to the ECM on two separate wires (presumably one wire for each bank).

If you have a fast-reacting voltmeter, what voltage do you measure across the battery terminals while cranking the engine? If the voltage falls much below 11V while cranking, the ECM may not trigger the ignition consistently.

Jags are known for exhibiting weird hard-to-diagnose issues due to corrosion on battery power connections (especially the false bulkhead connection and other engine compartment connections) and/or grounds (you might start by cleaning the grounds used by the ECM).

Is there any chance of water on the electrical connector for the ECM, or water ingress in the ECM?

You mentioned that you applied dielectric grease to the tops of the spark plugs. Since dielectric grease is an insulator, I just apply a thin later to the inside of the rubber end of the coil to ease insertion and withdrawal without potentially decreasing the current that can flow through the plug. I don't remember if you did the greasing before or after your problems began, but next time you might want to reconsider the grease on the plugs themselves and just go with the light coat of anti-sieze on the first few threads. BTW in aluminum cylinder heads Jaguar recommends nickel-bearing antisieze instead of copper-bearing.

My instinct is that you shouldn't worry about timing until you've rectified the weak spark.

Hope to hear good news soon.

Cheers,

Don

 

Other than saying $hit will happen at anytime with our cars and the issue is one of several possible spontaneous causes ......the other moral of this story is 'NEVER LET ANYONE START UP YOUR CAR WHO DOESNT UNDERSTAND THEM'


'we' are familiar with a lot of issues when it takes a second or two more than usual to start the car. 'we' know about the risk of bore wash if they don't start and you keep cranking


after seeing how one bunch of spanner monkeys abused my car by revving it from cold one time I never let my car out of my sight when its in a workshop....


a tire monkey doesn't give a damn and will keep cranking til the battery is dead if it doesn't fire

 

Mr. Scimitar:
Exactly what does that mean? Do you have some special way you start your Jag-u-wah? I mean, really, aren't we getting a little overly dramatic here?

I do not notice any of my Jags to require a special startup procedure.

 

no nothing special....but when they don't start a person knowledgeable of their cars foibles is less inclined to carry on cranking when they know the engines are prone to bore wash.....not dramatic.

 

OK, well maybe I am not so sensitive to it, since only one of my several X-308s have ever experienced the phenomenon which might have been bore wash- And, oh yeah, BTW, I cranked it until it started!

 

I think we can rule out Bore wash. Mitch has said over and over again that he has compression. He has old tensioners. He has less than adequate voltage to the plugs. I think that's less of an issue than the possibility of bad timing.

But the extremely cold weather has to play somehow. I am just an overly curious analyst. Can't wait to see how this works out.

I Believe I agree with Ross. Crank it until it starts (or the valves collide with the pistons).

 

I agree. "Hotness" of spark detected visually is subjective. In this case, I was not suggesting cranking! If I had an X-308 with old tensioners with any mileage, I would not never crank it until they were replaced.