Hi,

2000 XJ8, 51K miles, original owner.

Prior repair: 12-2009 had restricted performance & rough running
DTC codes:

Generic:

P0354 Ignition Coil D, primary/secondary circuit
P0304 cylinder #4 misfire


Jaguar manufacturer specific codes:

P1313 Misfire rate catalyst damage fault - bank 1
P1316 Misfire rate exceeds emissions

My (former bad) mechanic replaced valve cover gaskets, spark plugs & seals & said Ignition coils were good. No help at all from the expensive repairs! Same/worse problem & same exact codes. Took to Jaguar dealer. Replaced Ignition Coil #4 and mass air flow sensor. Problem solved.

Yesterday, almost 1 year later, had restricted performance & rough running
DTC codes:

Generic:
P0301 cylinder #1 misfire

Jaguar manufacturer specific codes:
P1313 Misfire rate catalyst damage fault - bank 1

I am guessing that the trouble is now with a different ignition coil (#1)

I think I can buy one & install myself, seems fairly simple. I am not a mechanic but have done some repairs. I may even try to swap the coil from #1 to a different #, clear the codes & see if the old #1 coil is now causing a misfire in the new cylinder to confirm it is a bad coil.

Found these instructions for a ’99 XK8 & I think it is very similar:
http://www.ehow.com/how_4695000_coil...-xk-vdp-v.html

Questions:

Which cylinder is #1? (2,3,4,etc.)
Is the firing order relevant here or just cylinder number 1-8?

I would hate to replace the wrong coil due to ignorance re how they are numbered.

Does my plan make sense or am I missing something? I have read that when 1 coil goes bad it is likely that others will follow.

Thanks,

Steve

 

Steve,

the DIY instrunctions you have found is the way to go.
Perfectly described...

To swap the coil just makes sense if you have a code reader on hand.
Your idea to clear the codes, swap the coil and see if a code with a different cylinder # appears is common to check (or locate) coil failure.
But usually you can trust the OBD reading...

For the numbering of the cylinders you probably could refer to the diagram in post #8 of this thread... (Depends on VIN)
https://www.jaguarforums.com/forum/s...ad.php?t=38864

Good Luck!


David

 

While you are in there, you may want to look down in the bottom of the spark plug holes for evidence of oil building up down there.

If the VC Gaskets are leaking again, that could be the cause of the failing coils. The oil builds up down in that little pit and then the coils can short out and cook themselves.

If the gaskets are leaking and oil is built up down there, I've twisted a paper towel to a point and poked it down there to soak up the oil. If you dont care about the splatter, compressed air and a rag over the area works much faster. This will keep the coils from shorting out until you can get the gaskets replaced.

 

I have information on my page that might help http://www.gusglikas.com/AutoRepairTroubleShooting.htm Now as for the firing order http://www.gusglikas.com/images/Auto...sb_09_2003.pdf page 13. I hope this helps!

 

David, I had found that post’s link to a pix b4 but still cannot access, I think because I am new to the forum. I did find a diagram that I believe to be correct & will list link at the end of my post. I would just replace coil #1 rather than waste time swapping since the trouble codes are identical to the fixed problem by the Jag dealer last year except for the Cylinder number. But, I have a concern that there are two different coils for MY 2000 XJ8(see my other post “Ignition coil -- 2 different ones depending on VIN.”)

Sinister, you describe exactly what I was told 11-2009 by my mechanic who replaced valve cover gaskets, spark plugs & seals & said Ignition coils were good. No help at all from the expensive repairs! Now I did not look into the plug hole myself & perhaps he was correct that there was oil there & I did need new gaskets. However, he failed to detect the bad coil despite being handed a typed paper with the DTC codes. As mentioned, I took to Jaguar dealer. They Replaced Ignition Coil #4 and mass air flow sensor. Problem solved. No codes or trouble for almost 1 year & now it appears to be a different cylinder/coil. I will certainly note any oil & if there is oil I will assume that this former mechanic did not replace the gaskets but only claimed to do so & charged me. I hope that isn’t the case.

Gus,

I have saved the PDF for future reference.

The image on pg.13 is the same image I had found 2 days ago that had confused me since it also had red letters apparently added to a copy of the diagram from your PDF.
I didn’t understand why 1234 was repeated. Since I thought the cylinders were numbered 12345678 & not 1234 for bank 1 & then again 1234 for bank 2. See my link:

http://s127.photobucket.com/albums/p...8FireOrder.jpg


Bank 1 is left side when standing at front bumper. These numbers were inside circles representing the cylinders. Then it had numbers in red on the sides with 1-4 corresponding to the 1-4 for bank 1 & numbers 5-8 corresponding to the 1-4 for bank 2. 5 closest to the bumper for bank 2. Then it listed firing order at the bottom of the diagram. I think I can ignore firing order for this purpose.

Standing at my front bumper on the left (Bank 1) 1234 moving from bumper to windshield & 5678 on the right (Bank 2) moving from bumper to windshield.

I am ready to do my work.

I am going to remove all the stuff in the way so I can remove the cover. (Too bad it isn’t coil 5-8, much easier to access!) I will then switch coils 1 & 2. I will also take photos of the removed coil. I will note any part number. I will clear OBD codes & wait till the misfire code appears for coil 2 instead of coil 1. I also have a P0351 which should then change to a P0352 after my swap. Once I confirm it is in fact the bad coil, I will take my photo to AutoShack & see if their $108.00 part that they claim is OEM looks the same as my photo. If it does not, I will go to the dealer & pay the $ 167.00 for the correct coil.

Thanks,





---Steve

 

I had a similar problem with my XJR. Make sure to check the coil boots. I found that a few of mine were too loose and would allow the spark to arc. This was causing a mis-fire.

 

I figured out exactly which ignition coil model # I need (see other thread “Ignition coil -- 2 different ones depending on VIN!”)
So, I’m waiting till the new coil gets here before I remove air intake & get into the coil cover. I assume I will get a new boot with the new coil. It looks that way in the pictures.

I think you are trying to save me money by suggesting it may not be a bad coil, just a (much cheaper boot). The fact that 1 year ago Jaguar diagnosed my car with a bad coil & replacing it fixed the issue leads me to strongly suspect another bad coil now.

I don’t have the expertise to tell if this or any other coils are too loose. Unless the difference was drastic.

Thanks.

 

I received my coil from Gaudin Jaguar last Friday & replaced my bad one & it worked! Car runs great & no more codes. In case any others read this later who are about to do the same repair, I’ll detail a few things. The bolt sizes are for my 2000 XJ8.

Once you open the coil cover’s six 7mm bolts & remove the two 7 mm bolts holding the coil itself -- it was very difficult to unclip the wiring harness! I finally had to GENTLY use a screwdriver to pry it loose from the coil body. The harness easily snapped onto the new coil. Be careful not to dislodge or pinch any of the wires when replace the coil cover. I also wiped the area clean before I removed the cover.

Since I had to work on bank 1 I had to remove the air intake from the filter to the throttle body. I had 5 clips on the air filter box top to unclip, the MAF wire harness (again difficult to unclip), breather hose and two 8mm bolts on the top of the throttle body housing. In addition next to the bolt nearest the windshield, there was a clip attached to the air intake hose which held a stiff plastic tube. I had to remove the tube or else cannot remove the entire air intake assembly. The tube was in the clip very tight. On reassembly when I tired to push that plastic tube back into the clip the clip broke or fell off & was lost!

I am not sure it is even necessary as the plastic tube doesn't seem to be in the way of anything so not sure of the reason it was clipped. I called Jaguar parts to describe the clip & they need me to come in to look at diagrams.