Hello and greetings from sweden!

My first post here, and its a bad one

The car in question is an XKR 2001 with the 4L engine.

And now to the problem! The car runs OK when its idling. Sounds normal, feels normal. The problem occurs when you give it some gas.
The car feels really slow, like there is no performance at all. And if you give it full throttle, it starts to missfire. And then the check engine light goes on, and it reduces performance.

I got the fault codes read, and the codes i got was P1000, P1313 and fault codes for missfire on cylinder 1,3,4.

After i got the codes, i started to check the engine. Went thru all the wiring - seems OK.
Tested with new coils - Same problem

Had the car at the local Jaguar firm to check it, and they couldn't find it either. Their answer was - It's problably the ECU. So i took the ECU out, and sent it to a firm in england. They checked it, and i got told that the earth connections in the ECU was bad. So they fixed it and sent it back, and i installed it in the car.

Guess what? Same problem!

Started to tear the engine apart, to check for vaccum leaks, and found out that the EGR valve was leaking. Somehow it had melt ? There was a big hole in it.

So i replaced it, and i still have the same problem.

Another thing is that the car seems to get pretty hot, a little over average on the gauge, but it feels like its to hot. But i guess that it has to do with the un-burnd fuel going thru the catalyst.


So now my question is, anyone knows what to do? What to check next? Or maybe anyone even know whats wrong?

Greetings from Kent

 

Just a completely wild guess here but did you check the oxygen sensors?

Doug

 

Forgot to add that the local firm did try to change the MAF sensor, but without sucess.

 

Another random thought--did you check out the fuel injectors?

Doug

 

I had the injectors on the bank where the missfire occured tested, and the seemd fine.. :/

 

Why couldn't they change the sensor? , sounds too simple but have you tried a new set of spark plugs, could the camchain have jumped a tooth, it could explain the misfire if the timing is slightly out.

 

Oh they changed the MAF, but it still runs bad, so we switched back to the old one.

The sparkplugs are new.

I had the tensioners changed at the local firm to.

About the cam chain jumping, is it possible to see if it is correct by just taking of the valve cover? Or do i need to tear apart the whole front of the engine ?

 

It was unclear whether you had all the tensioners changed or only the secondary ones. The connections between the secondary chain sprockets and the cams are infinitely adjustable. Checking the timing on the secondary ones can be done with only the valve covers removed but really requires the cam lock down tool to hold the cams in place.

 

I dont see how it would be possible for cam timing to cause this. Think about it either 1 bank of the engine would be affected, or both banks. Not some of the cylinders from both, so rule that out. Start by performing a power balance test and see if there is an imbalance. You have to think what do these cylinders have in common for them to be the ones affected. If it is due to overheating, (and I hear that can happen with out much warning from the gauge) you may have a headgasket issue. I dont know how the cylinders are labled on this car (even on one bank and odd on the other, or 1thru4 on one bank and 5 thru8 on the other) If someone will chime in with that info I maybe could give more insight.

 

They changed the secondary tensiorners (The ones on top).

Got the valve cover of today, and i noticed that the chain on the B bank is tight, but the chain on the A bank is loose.

And the tensioner on the A bank seems to be stuck? The one on the B bank is movable (you can push it in, and then it goes out again) but the one on the A bank is impossible to move.

Shouldn't it be possible to move it without oil pressure ? Seems a litte wierd to me.

And about the camshafts. Are the "flat" marks supposed to be in a perfect line ? Because it seems to be off at the A bank (probably because the chain wont tense)


Ordered a workshop manual today to. Hopefully i will figure this out :/

 

The 'A' (right) bank ends up with the flats slightly out of align and the chain a little loose due to the pressure of the valve springs on the lobes. That's why you must use the lock down tool for correct cam timing.

I would think that you should be able to depress the tensioner without oil pressure.

 

Figured out the timing now, and it all seems correct. So i guess that i have to keep on searching!

Any tips of where to go next? :/

 

I would listen to this guy, I hear he diagnosis running problems for a living and is pretty good at it!

 

Going to test the fuel pressure tomorrow. Anyone knows what the pressure is suppose to be?

 

JTIS says 3,0 bar.

Looked that up and 3,0 bar equates to 43.5114 psi. Seems high but that's what the book says. Don't know if I have seen a pressure gauge that reads to four decimal places.

JTIS also had about a page of cautions on the various ways to blow up the car and yourself messing with the fuel rail (up to and including death).

Anyone involved in loving a Jaguar this much needs a copy of the JTIS CD.

 

I have a copy of the JTIS CD now

I have another question. It kinda feels like the ECU is killing my coils. Changed to coils (switched side on them = a bank coils on b bank, and vice versa).

And then i did a test run, and still got the missfire problem. But now it also included missfire on the b bank cylinders, aswell as the a bank cylinders.

So it feels like there is something in the ECU that kills the coils on the A Bank.

Had the ECU repaired, but it kinda feels like its still broken. So now im thinking of getting another ECU, but they are really hard to find.

My ECU number is LNG1410AD. The only ECU that i can find in Sweden is labeld LNG1410AC.

Anyone knows what the AC / AD stands for ?

 

That is usually a revision number. i.e. AD is a newer version of the AC.

 

Fuel pressure cannot cause some cylinders to missfire, it would effect all of them. Do a power balance, by pulling one coil connector at a time and see which cylinders are running, then swap coils and see if the cylinders change indicating coils. if not it may be the drivers in the ecm.

 

Hello again! Some time has passed since i last wrote here.

I need some more help. I tried again to swap the coils.

The funny thing is, that i had problems on 3 cylinders before. But when i swapped the coils, the problem occured on 6 cylinders! So it seems to me like 3 coils are dead, and the ECU is the killer. Is this possible ?

Anyhow, i bought 8 new coils, sent away the ECU (AGAIN) for reparation.

Got it back last week, put it in, with the new coils. Guess what?

It runs even worse now. Instruments are not working, poor idling, cant rev the car, the car goes into "safe mode" etc etc.

Anyone have some tips ? Starting to get really frustrating.

 

Read the fault codes now.

P0010
P0020
P1637
P1638
P1643
P1797

These are the codes i get. The four last ones are pointing to CAN errors. And i have checked all the cables, twice.

So to me it seems like there is something wrong with the ECU.

I also mailed the company that repaired it, and they said that they changed it to a replacement ECU, and filed over my old software into the new one.

Funny thing is that the car is not even usable now. Cant even get it of park, engine is in fault safe mode, ABS/EBS is not working and so on.

It also say that the wrong part is installed - guessing that it is the ECU