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04 xb spark plugs and major oil burning

I have an 04 xb with about 157k miles. At around 146k my car started to lose power and feel like it was going to die. Got a misfire code on cylinder #1 after having the engine light come on. Replaced all the plugs and everything was like normal again #1 plug though had disinigrated and that’s the cylinder that pulled the misfire. Cylinder 4s spark plug was real bad too but not as bad. Cylinder sleeves on the valve cover where the coil packs go we’re all oily on cylinder#1&4 but clean as a whistle on 2&3.
Drove the car another 5k miles or so and all of a sudden started burning oil over a 1qt per 1000 miles. I just started to notice oil on the engine cover by cylinder #1 that I didn’t notice back 11k miles ago. I know I need to check my pcv valve but is this a BIG problem or just a few little things? I don’t know if I drove too much with the car being like this and should cut my losses or try to fix it.
Here’s the pictures of spark plug 1 and 4 which only had about 30,000 miles on them. Thanks for any help or advice I appreciate it.
I also did a compression check at the spark plug change and each cylinder was around 152 to 156psi.

The missing ceramic was left in the engine when the spark plug was replaced? If so, I wonder if you scored the cylinder wall…

I tried to suck, blow, and use a magnet as well to get any type of particles out of there. There’s a bit of dust and little shavings I got with the magnet but I think whatever happened to it had already been done. The car still gets 32+ mpg

The first thing you need to do . . . replace the valve cover gasket and the spark plug tube seals

Just replace the pcv valve . . . you could go crazy, trying to figure out if it’s working or not

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See if you can borrow a “borescope” (also called a “fiber-optic scope”). Examine the cylinder as best you can. I fear TT may be right. If that ceramic and the metal electrodes came out in the cylinders, there’s an excellent chance of cylinder damage.

After that, I would not spend any money on the engine until I’d tested the cylinders for both compression and leakdown. I’d bet that at least one won’t hold pressure. If I’m right, you’re looking at a teardown and rebuild… or a replacement motor.

Post back.

So it sounds like it might be worth just taking it in and having it looked over professionally. I don’t want to put more money in it but I’d rather be sure than just assume and put more money in only to end up in the same spot in a month

Sounds like a good plan. Bring the shop the sparkplug photos too, and tell them the whole story.
Let us know how you make out.

Any damage to the inside of the cylinders was done the second the spark plug broke. There’s nothing you can do to clean it out now. And what’s done is done. My advice at this point would be to reseal the valve cover and spark plug tubes, replace the PCV valve, and install new plugs and coils (because of the oil contamination). Then drive on and monitor your oil usage and see how often (if) the spark plug fouls out. If the oil consumption is stable at 1 quart every 1000 miles, keep driving. You can buy a lot of oil for what it would cost to fix the engine. If you’re fond of the car and it is in otherwise good condition, drive it until the oil consumption is unbearable and look for a good used replacement engine.


… and be sure to use the exact same plugs called for by the carmaker - which may not be the exact same plugs that are in there now.

Thanks to all. I think I’ll order the parts and have them ready and decide along the way if I’m going to pursue the run until she dies and do it myself or pay up to someone else to hear the same thing. I did use a little bit of an upgraded plug that other xb owners have had great results with but I will be going back to bone stock just to eliminate all causes.

Well, that ceramic isn’t just going to disappear. It may get pummeled enough so the smaller chunks get ejected out the exhaust but some bits may remain. I would at least use a borescope to look in there and see if any pieces remain. My concern would be that huge chunk broke loose and got between a valve and the piston.

Then there’s the larger question, why did it break off in the first place? Detonation is often a cause of this kind of failure. Or someone dropped it on the floor when they were handling it…

What brand of plugs are these that failed?

Ngk spark plugs.

That is my fear as well is the plug continuing to do this if I don’t figure out why. But i know the oil and the plugs might be issues hand in hand.

That kind of spark plug damage can be caused by detonation and cylinder overheating. Ask your shop to check for that. Things that cause detonation to look for are improper plug gap, faulty ignition timing, faulty knock sensor, using wrong fuel octane, lengthy & rapid accelerations, long uphills at full power, long periods of high rpms, overly lean fuel mixture, faulty ignition system or wiring or coils, faulty cooling system, carbon deposits in cylinders, etc.