I have left my XK8 at the dealer in Vancouver for over a month and they are still struggling with getting the engine running. I originally took it in for a tune, because it lugged when accelerating above 105 kph. After a couple of days in the shop and with new plugs in place, it actually would not run at 30 kph and really not at all. Needless to say, it went back on a lowboy.

They have struggled with it since. They currently have the valve covers off and have found the variable valve timing on the left bank seems to be screwing up to the point of the valve hitting the cylinder head in the front cylinder. It seems the right bank is ducky. The adjusters, guides and timing chains were upgraded to the metal components just before I bought the car. It seems for some reason that the left bank timing solenoid is screwing up.

Does anyone out there have any experience with this? The solenoid just seems too simple to fail. Frankly, the service manager has thirty years Jag experience and is scratching his head.

 

There is a oil viscosity concern with the VVT actuator or it may just be stuck . You should be able to apply 12 volts to the solenoid and watch it ( solenoid only ) actuate . Without looking it up a 4 wire stepper motor used a a solenoid would test different the a 2 wire open /closed solenoid . As to the actuator that would be harder to move as a test . Open wire between the ECU and the VVT solenoid ? Might have to double check the AJ26 and AJ27 engine range as there was some wiring changes .

In your climate the right viscosity would have to also match your outside environment but since it's summer you might use the optimum viscosity for VVT operation .

 

Valve hitting the cylinder head? Which is fine.

Valve hitting piston? Definitely not fine. Assuming someone misspoke, it seems you are dealing with some sort of valve timing issue. Has the dealer checked the valve timing (easy to do)?

Could you replace the VVT with an eBay part (imagining a new replacement part would be uber expensive), if that is the cause of the problems?

 

Are they able to provide a list of diagnostic codes? Most of these components are monitored and should provide specific codes when they fail.

 

I'd have a real concern with an (ostensibly) experienced dealer who can't resolve this after a month of head scratching. Perhaps something was assembled incorrectly with the tensioner R&R, as I'm fairly sure that the vvt units would n't allow enough range on the inlet to allow piston to valve contact. Dealer really should be able to troubleshoot this. I doubt the solenoids are the cause.

 

If the mechanic is saying that the VVT is causing the valve to hit the piston then it's time to find someone who understands this engine. VVT only has a 15 degree total movement on the camshaft. No way that set properly that can impact any of the other moving parts.
Either the cam timing is incorrect, the chain is stretched or the secondary tensioner has failed. I experience a tensioner failure with a brand new 3rd generation tensioner in only 2 weeks after installation.
They need to run both a dry and wet compression test on the engine. If the valve has impacted the piston that cylinder will be dead. No compression. Due to the performance issues you were having I would suspect the the valve timing is off just enough to affect performance.
Because chains and tensioners were changed is not an indication that they were done correctly. With the covers off both tensioners should be taught against the chain. Start with the basic's and lock down the crank and check valve timing.

 

Thank you ALL for the replies. Yes, I too was concerned that the biggest dealer in the country still was working on this problem after almost five weeks. The ONLY reason I have left it there is that the service manager has SO much experience and that they promised to make it right without putting me in the poorhouse. Having said that, they are going to have to eat a TON of labor on this - but frankly, this should have been fixed overnight.

He (the service mgr.) has said the front piston is ok and that they will check the solenoid today. The VVT on the left bank is NOT OK.

I drove the car all last summer and it gave me all the performance I wanted, including taking her up to her top speed just to see where it was. The car was an absolute delight. It did not stop running until the dealer tuned it.

I will forward your thoughts to the dealer because I think a few of you had really great ideas. Lady Penelope - I think they are actually going to be doing as you suggested today. And Avern1, I will certainly suggest they have a second look at the things you mentioned.

Thanks again, everyone!

 

There was a thing about a certain brand of oil filter collapsing internally dropping the oil pressure lower to not be able the actuate VVT's and timing chain tensioners properly .

 

Does anyone have access to a Windows 10 JTIS (Jaguar Technical Information System)? I have the Windows 8 compatible version which will only run on my old laptop. I would VERY much like to be able to run it on my tower which is 64 bit Windows 10. Go figure JTIS is not upward compatible. I would give my eye teeth for a newer version even though it is for an old car - my '99 XK8.

 

You should be able to get Win10 to do it - if Mickeysoft didn't break Windows (again). Do none of the various descriptions about how to do it not work?

There may be PDF versions (as there are for my car) or worst case a used laptop without Win10 can be had cheaply.

 

I actually have a nice little laptop which I use for diagnosing the car but I have old eyes and my Windows 10 tower has a 32" screen which would make reading the damned small print a great deal easier. I found a pdf version to download but to get it I had to install a whole bunch of very messed up software which screws with searching among other things. No thanks. If someone has access to a clean pdf copy I would be thrilled...

 

Usually you can plug a laptop into a big screen.

(Or use reading glasses.)

 

Let the bells ring out and the banners fly! The Jag dealer finally found the problem. It seems one of the eight ignition coils has failed. I am amazed that did not immediately generate a unique error code. It also seems that the catalytic converters are somewhat plugged. That is what has caused the check engine light. Again, I am surprised there is not a unique code for plugged catalytic converters. Well, at least they can be punched out and give me time to find lower cost replacements than full retail dealer price. If the check engine light remains on, I can live with it until I find the parts I need.

Now the issue is what the bill will be hunting down what I would think would be fairly easily diagnosed problems. I know the dealer tech put in huge hours - or they say he did. After all, they pulled the cam covers looking for bad coils...

What do you guys think I should say to them? I am really very interested in your opinions.

 

Sometimes you rely on gizmo tools to give you a target , but you can never forget the foundations of engine regulation to be covered first . The difference between a mechanic and a instructions follower .

 

I have a friend that operates a MB indy shop and he told me that the dealer sends him cars that are over 10 years old because their (the dealers) mechanics are totally lost if the testing equipment doesn't nearly pin point the problem.
I personally wouldn't feel indebted to the dealer if the dealer networks are all operating like this, just a thought to consider.

wj

 

There ARE codes for these things. You can see people have posted them a lot.

 

After five weeks in the shop and thousands of dollars in "repairs" - deeply discounted so I could actually manage to pay, MCL Motorcars in Vancouver had me out on the highway, my car in the traffic lane because of Jersey Barriers and a very narrow shoulder, with no throttle response and me screwing around in the engine bay swapping relays about, cars whizzing by at highway speeds. If you want an exciting drive, take your car to this dealer. Now imagine trying to make a four and a half hour drive when you have to find a place to stop every five minutes or less and turn the car off to let it "cool" or "rest" or something, to give it throttle response once again. Oh, and did I mention the bazooka-like backfires, when gearing down? No? In the end, a four and a half hour drive took nine hours. That was with multiple opportunities to risk my life in traffic. Truly a desperate drive - losing throttle response on the highway.

So, the question remains - what the hell is wrong with my XK8? MCL Motorcars obviously has no idea and it seems the car did not generate any error codes for them. I have "check engine" and "restricted performance" lights so one would think that would give them a clue...It seems they did not take the car out for a drive or they might have had MY experience. And the question remains also - now that my bank account is emptied, and NO repair performed - how do I afford to actually have the car repaired? Here it is summer and my lovely XK is not driveable. Should I take MCL Motorcars to small claims court or just demand my money be returned? Or, am I simply out of luck because of the car I drive? So many questions...

 

Have you discussed these issues with the owner of MCL Motorcars? If not, why not? If so, and he told you to go pound sand, then I would be filing the necessary documents to take them to court....

 

So i can sit here miles away and give my opinion. This happened to me, a local Jag shop kept the car when i first got it for 3 weeks, cost me $1900 and all they did was change a coil pack, fuel filter, mass air meter, and the plugs and the car would not pass smog!!!! My original complaint and I am glad they did what they did but it's a few hours job....not weeks.

i then found this forum , got a new battery, and then went to work on what was wrong. Car passes smog now and runs well.

The dealer you took it too was out of their league with this job, should have told you that sooner but since you are a long distance customer and was in no hurry they wasted your time obviously.

I would simply take this to a small shop in your area that understands auto repair, the jag is not Lambo or Ferrari unique.

It's probably a sensor or an electrical issue an electrical shop can repair. I wish you luck.

 

With a CEL on there should be codes to read!