My lovely car presented me big surprise today, by leaving my in the middle of nowhere with constantly stalling engine.

Short review of my problem - couple weeks ago my car died at the junction.
Started engine again, everything works perfect. I gave no attention to that.
After a week the engine stalled couple times a day.
The symptom got worse, stalling engine occurred more often. Sometimes couple times a day , but after restart was all good.

Today everything happened while driving, engine started loosing power, revs dropped down. Check engine light flashed but didn't stay on. Tried to restart, but car dies after 10 seconds or more. Many restarts made, she runs for some time and stalls.

Had to tow the car for 50 miles back home, wonder if I couldn't damage the transmission.

Interesting that when I got the car back home, started and voila she runs smooth again. . But till the next corner she will die again.

My wonder is do i have starting to have issues with failing cps or could be something else.
Coils are changed one month ago, so i would skip coils as an issue. Engine runs very smooth. I heard that cps fails slowly and might have such symptoms.

Anybody had experience with cps? What the usual behavior of that?

 

Cheap coils will put dirty AC electricity in the cars DC wires and make the car go freaking nuts . Do you have the old coils ?

The CKPS will fail on a partial basis effecting things like the fuel pump control without giving a code .

You can hot wire the fuel pump to troubleshoot this possibility and test drive it staying close and uphill from home

 

Lady P. could you please explain what you mean by dirty AC electricity from cheap coils? I had seen you mention that a couple of times and was wondering.

 

CPS will usually start failing as they got hot, once they cool down then you can restart, but will only just cut out again once hot.


Mine was doing something similar to yours, cutting out while driving, and not starting after sitting over night or after shopping. Eventually it was cutting out more consistently, and found it was the fuel pump. Which at this point I would just get out and give the fuel tank a good bang with my hand and started right up.


If it cuts out again, and you're trying to restart it, check the Tach and see if the needle moves to around 200 RPM while cranking, if so, then your CPS should be ok. If not, then you probably need a new one.


You should be able to hear the fuel pump running when turning the ignition on.


CPS is quite common with X300 and XJ40's.

 

Sure ,

More more then one kind of electricity or signal can exist in a wire at the same time and the device on the other end of the wire can see all the signals unless it is filtered out . Cable TV works in this manor as you buy certain viewing packages . Old school Vacuum Tube amplifiers for electric guitars will only work with 2 signals in the wires at the same time , one being the AC sound signal and the other being the amplified DC signal later being filtered out before the speakers .

There is a cool and easy to follow Youtube video on how they work if interested , I learned alot from it .

The dirty electricity comes as they short out as a pulsating frequency

 

Leaving no code and cut fuel pump, this might explain weird very sudden engine cut off situation.
Aftermarket coil issue i would discard for now, because last year i had also replaced them all and till they were good engine ran very smooth. When thay started failing engine just ran poorly with misfires but the car was running.
This time I have sudden cutoffs, blinking check light, and no error code.
I have some old coils left but they were running poor.

Ordered new CPS sensor for now, keep you informed guys.

 

I had similar experience with my XJ40 which turned out to be a wiring issue with the CPS, the insulation was frayed and occasionally the signal would get diverted to earth. Invariably I was first in the que at traffic lights. A quick shift to P and restart normally saw me mobile again.

 

Seems a bit slow for a failing CPS. Mine failed all within a few hours, had been fine up till then. Got a complete brief cutout a motorway speed, got to where I needed to be. Came back to the car and it was surging in park. drove for another mile or so and then cutout. restart, but instant cutout.

 

Hi RB_jaguar,

I've been mulling over your posts, and I'm not sure you've begun your account at the right point in time. If I understand the chronology, two weeks before the car stalled at the junction, you replaced all six coils. It might help us to know the behavior that prompted you to replace the coils. Was the engine misfiring and were misfire codes flagged (P0300, P0301-P0306)?

Speaking of codes, how recently have you scanned for them? In most cases when the Check Engine Light illuminates one or more codes will be stored.

Just because the behavior is different now, don't be too hasty to rule out the coils, especially if they are not the OE Made in Japan ones by Diamond Electric Manufacturing Corp. Malfunction modes aren't always the same, and often stalling is due to more than one component malfunctioning.

Also, have you done any basic tests on the fuel pump and its circuit?

I'm especially curious to know what prompted you to replace all six coils a month ago.

Cheers,

Don

 

Hi Don,

Actually coil issue happened much earlier. Couple months ago car started to have constant misfires, while driving. Especially when was cold outside. I had some spare coils, started to look for what was faulty one. That didn,t gave much success because all coils where already to the end point. Swapping, inserting new one between old ones didn't eliminate misfiring and rough running.
So i decided to change them all new. And it helped. Since then engine runs smooth, and till now had no misfire. Stalling came much more later, so thats why i don't think it's a coil issue.

Had to mention that there was no at least one error code, while coils were misfiring. I just get constantly p1621, but thats a ghost what don't understand.

I checked today after stalling issue and again i just have p1621 code.
When cold, car starts and runs great,as if nothing happened.

I didn't tried yet hotwiring the fuel pump, because of lack of time, just ordered new CPS hoping that helps.

 

UPDATE

Hi Guys,

So after change the CPS sensor, things didn't went away.

Interesting thing that cut offs start after some time driving and when they start got worse and worse till car dies after each restart.
When car cools down, again she drives smooth.

When driving along, engine cuts out for a second, usually get "check engine", but recovers instantly with a bit of throttle applied. After that no codes are stored.
Cut offs happens under acceleration, and at idle.

The scenario is - car cold starts with no problem, i can drive for about 20 -30 minutes , everything works. After 20 min cut offs start. The more time since then passes the more cutoffs i have, till i'm not able to restart it. Then wait for an hour and everything goes around again.
Interesting is that engine warms up fast and cut off is more related not to engine temperature but time.

I have read some post with similar issue, and its complicated because many of them didn't managed to find the issue.

This is the video from other post with exactly same behavior, except im my case no gearbox light illuminates.


I'm hoping to be lucky find it to be the fuel pump issue, if not I'm in big trouble.
Will try to swap relays of fuel pump with AC first.

Any suggestions.

 

 

Hi Vee,

I have obd scanner and it reads the correct data 86 degrees C.
I have changed the Crankshaft position sensor, not Camshaft.

 

Per the Jaguar service documents, when the AJ16 was introduced with with position sensors for both the crankshaft and the camshaft, to avoid confusion Jaguar did away with the old CPS abbreviation and adopted CKPS for the crank sensor and CMP or CMPS for the cam sensor.

Cheers,

Don

 

If the problem is temperature or time related, it could be anything ranging from temperature sensors (engine, air, coolant....), airflow meter, even to the ECU. On one occasion it was the CKPS as it got wet once during a small flood on the road. Cold start was rough but car would stall when hot and refused to re-start. On another occasion after replacing the CKPS, I had problem re-starting the car when hot or warm. Thought it was fuel related: the purge valve in front or Rochester valve at the back, but when the car eventually died it was later found to be a corroded ECU. Replacing it sorted the problem.

 

Update follows.

So after lots of thinking, made some tests wits relays.

Swapped ecu relay with AC relay. But that gave no result, the car still was in trouble.

Made some tests with fuel pump, also same result.

Checked with obd scanner temperature once more, looks good.

Decided to go to fundamentals, remembered that month ago I changed all ignition coils to new ones. I used cheap ones from USA ebay. Set of 6 was maybe 70 US dollars.
So drove the car to that moment till engine started to cut off, pulled over and changed then all coils back to old ones, some of them were original some not but still workable.

After that drove all day round the town, and no more cut off.
I dont know did it solved the problem but , for now all good.

If its coils I'm kind a confused because now i have a dilema where to buy them.
Original OEM are to expensive, cheaper ones Im afraid to buy now.

Anybody please share your experience on coils from britishparts.co.uk.
Also meat and doria coils for 80 euro/peace, anyone tried that?

 

OEM 'Made in Japan' with a 3 Year Warranty

https://www.sngbarratt.com/fr/#!/Fra...8-617ea71443cb

This is the one recommended by many as the " Made in Japan " . I haven't used them yet . There is a discount for forum users somehow can be applied . If you can swap the positions around and maybe find one that is bad and replace that one it lessens the financial burden and buy one a month . Motorcarman ( Bob ) had a trick of watching them at night and seeing the defective shorting coil in the dark .

Cheap coils induce a bad power signal into the car that can cause freaky things to happen that can't be diagnosed in a traditional manner .

 

Hi guys,

Found some ignition coils on european market.

Does anybody tried those ones? Any luck with that?

Meat and doria
https://www.autodoc.de/meat-doria/7754129

NGK
https://www.autodoc.de/ngk/7006591

 

I am using QYL brand coils on my xj6. Amazon has them for $79.00 for a six pack! I have had them for about 10 months and so far no problems. They also came with the paper gaskets for each coil.

 

That's a classic ignition spark plug/ignition coil fail. Either you have wrong spark plugs fitted(I've seen this happen with Bosch Super 4 plugs, X300 just doesn't like them) or failed coil. Make sure to use normal Champion or NGK plugs and swap one coil at a time, ideally when its misfiring so you can see which one straight away.
I had exactly the same issue few weeks back, first cylinder(from the front) coil fail, RPM was dropping as soon as the car got up to temp, swapped it on the side of the road and drove home fine. I always have a spare coil in the boot and CPS now.