First post here! I have gained a ton of knowledge about my new (2004) X-Type since owning it for the last few weeks. I have been doing all the maintenance updates including fluids, filters, etc. Last night I decided to take off the intake and tackle the spark plugs. What I found had completely puzzled me. I am 40 and have been working on cars since I was 15, but haven't seen this one.

As you can see from the pics, the rear openings for the ignition coils were coated in grey powder. It also looks like the far left opening had broken, melted, around the opening? Also on the rear valve cover around the edge of one of the bolts it looks like the metal had been blown open with more of that grey (looks like carbon to me) coming out. I'd like to just buy a new valve cover, but for $370.... . I did open the cover and there are no internal problems, none of that grey stuff either.

You think the cover needs replaced? I was planning on installing all new valve and spark plug gaskets. Is this due to oil spraying out under pressure? Coils arcing? I just have no idea. (pic attached with the normal bolt too for example)

Thanks for the help! (typed on a cell phone)

 

I forgot to mention that the intake manifold had (to much for my liking) oil pour out of it when tipped on It's side. I'm assuming that is a bad pcv valve causing that. Has no idea if that has anything to do with the first problem.

 

I can't be the only one that has seen this?

 

I've never seen that but I am not a mechanic.

However, that rear passenger side plug opening is known for filling with oil, so I think your theory of arcing is probably correct.

The owner must have put up with a lot of misfiring.

I wonder about the condition of your cats.

 

Hey, thanks for the reply. Yeah, I'm just not sure if super heated oil would turn into carbon like that or not. Burned oil turns black I'm pretty sure. Electrocuted oil....no idea. Either way I ordered all of the gaskets for that area, top and bottom for the intake and the gaskets for the plug area and outside on the valve covers. I wanted to order new ignition coils too, but they are all working and I'm a bit strapped for cash.

 

I'd be surprised if a coil could put up with that much abuse, so I'd consider a new coil for that plug well, at least.

The oem Denso coils are expensive, but Chinese coils appear to be improving in quality and are less than $20 bucks now. I got a Chinese Delphi coil for $26.

http://m.ebay.com/itm/Brand-New-Igni...452?nav=SEARCH

 

Just ordered through Rock Auto. 6xDelphi at $23 a piece.

 

ebay has a bunch of rear valve covers for around $50. If the old one is a little warped, there is a good chance that it is going to keep leaking into the plug well.

With that much damage around the coil opening, you might want to male sure that the cover is still flat on the bottom.

 

I will check it out again. All of the Ebay valve covers looked horrible compared to mine. Mine are painted black and look decent. The Ebay ones weren't even black.

 

When I look a little more closely at your valve cover, it looks to me as if the valve cover itself around the coil opening is vaporised. Because the gasket is so close to that opening, I'd be surprised if the seat for the gasket is not compromised. You'll know for sure when you remove it, I suppose.

Thermo or someone is probably more knowledgeable than I about this, but I am guessing that the other spot on your valve cover that is trashed was probably the path of current through it from the head to the spot near your coil that is no longer there. So, maybe there was not oil in well after all.

I'm just speculating.

 

Holy crap! I'm glad I didn't touch it while it was running! I think you are dead on with arcing. From the look of it, it probably arced over to the other plug hole a bit, and over to that bolt area (if it was only one bad coil). I can't believe how well the car ran like that!

I guess the good news is when I'm done, it ought to run like a million bucks!

I looked at the cover again. Yeah, all the damage is external, not internal thank god. Like I said to begin with, I don't want to spend $400 on a new cover.

Thanks for looking at it!

 

Just for anyone's future reference....
2004 Jaguar X-Type 3.0L (US) 71,000 Miles
Still had original Denso coil packs and plugs

 

Well, it may not have been happening when you checked it out if the engine was running smoothly.

I wonder what would cause that though.

Keep an eye on it after you get the new plugs in there.

 

You bet I'll be in the dark looking for sparks!

 

 

I just borrowed my buddies code reader. When I slap it back together I'll make sure to check previous codes and live feeds. I'm guessing it was just old and worn out coil packs that were just spreading electricity. Crazy stuff.

Thanks for trying to help me out man!