fuel trim either long or short +/- is the amount of fuel either added or subtracted from target. short term is what you see if you remove a hose to create and vacuum leak, long term is a long term fuel addaptation to comphensate for the leak if left that way for a period of time. Its how we diag fueling and air flow problems. Its also how alot of techs get in trouble after repairs. They fix a fault but either forget or dont know to clear long term fuel trim. This cannot self correct fast enough after the repair before you end up with a new fault. And yes overfilling creates too much "windage" in the crankcase. This is wear the oil is whipped up onto the cylinder walls from the rotating assembly so much that the oil rings are overcome and leads to oil burning

 

Few more details...

Haven't had time to pull the plugs (it is my wife's car and rarely is it around when I have time to look at it) but I did a quick fluids check this morning.

It has been about 1,500 miles since I last changed the oil. I made sure to top it off well (it actually took a bit more than the recommended 6.3, took closer to 7 to reach the top mark on the dipstick).

Today I checked it and it was below the lower mark on the dipstick. I only had about a half a quart sitting around so I put that in and it still was just below the lower mark.

So....I guess that means it has burned about 1 quart or so in 1,500 miles! This is much worse than before (unless the dealership was just topping it off and not telling me). It has been smoking a bit more but certainly not proportional to oil consumption.

No leaks - new garage floor doesn't have a stain on it.

Coolant level was still maxed out, so it doesn't seem to be using any of that.

I want to pull the plugs because if a cylinder is burning oil, that plug should be dark black and oily, right?

 

yes, on affected cylinder, either valve guides or rings. But I would say rings since you said it does more on acceleration when vacuum is low or 0, thats when rings let oil in combustion chambers not the gudes. Guides more at idle/cruise/light throttle. You may also want to try bottle and a half of V8 engine restore and see if theat has an affect on you oil loss. Iv had very good results with that over the years.

 

OK, well I pulled the plugs today and took a look.

Here are some pics of them:

http://www.xpanxion.net/tempimages/dsc_3425.jpg
Passenger side plugs, front to rear

http://www.xpanxion.net/tempimages/dsc_3426.jpg
Driver side plugs, rear to front

http://www.xpanxion.net/tempimages/dsc_3427.jpg
Closeup of a couple of plugs - is slight buildup normal?

http://www.xpanxion.net/tempimages/dsc_3428.jpg
This was the worst plug - driver side rear-most plug.

http://www.xpanxion.net/tempimages/dsc_3429.jpg
Another shot of that plug.

http://www.xpanxion.net/tempimages/dsc_3430.jpg
Doubt it means anything, but this ring of rust or corrosion was on the insulator of a couple of the plugs.

http://www.xpanxion.net/tempimages/dsc_3431.jpg
One of the cleaner looking plugs.

http://www.xpanxion.net/tempimages/dsc_3432.jpg
Cleanest plug next to the dirtiest plug.

OK - so I'm no technician, so can someone interpret these plug appearances for me? Is there anything here of concern? I was really expected to see one really oily and dirty - one is certainly worse, but not sure it is THAT bad ... just today my wife brought traffic to a standstill when she pulled out and blew clouds of smoke. The engine also missed and hesitated while blowing smoke. She didn't notice a check engine light, but that doesn't mean a whole lot.

Thanks for any help, once again!

 

Well I don't understand, the severity of the symptoms you gave in post #1 should have led anybody who knows what they are doing to check compression/ cylinder leakdown as Brutal suggested in post #13. That's when they would have seen the oil-fouled plug you pictured, which isn't going to get individually affected by a PCV valve problem.

My suggestion would be to open a dialogue with Jaguar about the history of the vehicle, and request their recommendation for another dealer to inspect the car. That's about as much as I can say with my tongue held.

 

So that plug is definite proof that the cylinder is burning oil?

 

I have a compression tester ... can anybody give me quick instructions for performing the test? It has been a while.

As I remember, pull the fuel injection fuse, screw the tester into the bad cylinder, and crank for 10 secs or so...check reading immediately and then after 10 seconds...something like that at least, any guidance would be appreciated.

 

To what end? If the test is not conclusive, nothing gained. If conclusive, are you going to rebuild/ swap the engine yourself? It will still have to be verified by a dealership, who will then have to be convinced that you have a free engine coming.

Or it will convince you to dump in some "rings in a can" and heavier engine oil in, and sell the car if the symptoms subside a bit and you think you might get away with it. Sounds to me like that is what the last guy did.

You can check compression as in your description above, but the "10 seconds" thing is of no real value. Any slight pressure loss past the gauge's schrader valve or hose fitting might mislead you into thinking you have found a clue...that sounds like some poor man's cylinder leak down test, and it is meaningless.

Top up the coolant and run the test with the cap off, any head gasket leakage will cause the level to creep above the top of the neck if you should test an affected cylinder. This general tip will not show any result in your case, since you don't have a head gasket problem. Check compression with the engine fully warmed up, all plugs out, and go back and do them all again after squirting four strokes from a pump oil can (with a hose attached to enter the spark plug hole)in each cylinder, one at a time. You might see a meaningful indication, you might not. I don't see the logic in the exercise of attempting to collect more data yourself, when the evidence of a missfire and clouds of smoke hasn't prompted anyone to fix your car. This situation requires administrative, not personal, intervention as I read it.

 

Ide have to agree with JTO, and the plug on the drivers side is definitly your problem cylinder. Ive seen better plugs on engine with over a 130k, THAT IS A PROBLEM.
you need to contact Jag and quit BSing with the dealer youve been going to, someone doesnt know what theyre doing or been trying to pass the buck and hoping to get rid of you....you do have an engine problem and its not the crankcase system

 

Thanks for the input and candidness.

What is the most likely cause and remedy for such an issue? Only an engine?

What is the cylinder number for the cylinder closest to the passenger compartment on the drivers side?

 

Right bank = A bank = bank 1
Left bank= B bank = bank two.
The one you asked about is 2-4 (B-4)

It has a broken ring, or piston/ bore damage. The history suggests a birth defect. Any internal engine problem can be fixed, Jaguar apparently decided long ago that the most cost-effective repair at the dealer level was replacement. Pending confirmation, I think that is what you are entitled to.

 

What is your experience with Jag handling out of warranty vehicles with documented issues during warranty?

Warranty expired Dec 9, 2008 - based on time, not mileage. I have two documented service reports from my dealer describing problem prior to 12/9/08 and a documented complaint from previous owner from before that.

Is it up to Jag or the service manager, or a combination of both? Any suggestions on approach, since you guys deal with the symantics of it all the time?

 

I do not, I am an independant shop owner/ operator and have no interaction with Jaguar.
All of your questions should be directed to Customer Relations, perhaps Brutal can give you a more direct route. Try 800-4Jaguar, I think that's the best way to initiate communication. Demonstrate cordiality, evidence, and resolve. Good luck.

 

number 8, and yes an engine, the person that ultimatly needs to approve is the regional service manager for your region. And this is the route you need to go, wether you talk to him or not is not important, but he's the one to say yes. Get all documentation, dont do anything else to the engine other than putting back together. And start a case, like jto, and my mother says, you catch more bees with honey than vinegar...but be firm and know what the end result should be. Everyone at the dealer level is not gonna be able to help, time to go corp.

 

Brute, thanks for the backup. Hopefully the blokes will do the right thing.

 

Took it by the dealer this morning.

Service Manager took a look at pics of spark plugs, my notes about oil change/consumption, and history of vehicle (previous customer's complaints, also my complaints and the resulting PCV valve changes).

We also went for a test drive, and when I pulled onto the expressway we blinded a poor van behind us due to all the smoke. His only response was to stare and look at me like, holy crap.

He is going to call the factory and schedule an appointment with their rep in the next couple of weeks so they can pull plugs, compare notes, and figure out where to go from here. He did say he has a great relationship with the rep, but other than that he didn't say a whole lot other than it seems a new engine will be the only real fix.

I will keep you all posted. Thanks for all your notes and explanations. It was just really hard for me to imagine that the dealership missed all this in the 3 times I've had it in for service on this problem. The SM and techs are really cool, I just get the impression you have to nudge them along to get any real work done. Doesn't make a lot of sense, a new engine when under warranty would have been a cash cow for them...now it will be a headache for all of us.

Any other tips anyone has, keep them coming. I hesitate to call Jag directly because of the great way the Service Manager always treats me, my gut says to let him handle it initially.

 

The suggestion I made to circumvent them was only made when it sounded as if they were not taking appropriate action. Now they are.

 

Question - do either of you have the capability to pull the service history and see what was done at what mileage, with what complaint? I would like details but unfortunately my dealer didn't do the original service(s) and the dealers that did will only give me info over the phone, nothing in writing.

I can PM you my VIN if you do have that ability.

 

My part of that is answered in post #33 above.

 

Car goes back to dealer tomorrow. Jaguar rep is going to take a look at it and see what they will do.

Problem seems to be getting exponentially worse - I am adding a quart of oil every 400 or so miles now...