Hey everyone,

This is my first post on here; I've run out of ideas and need help. All my searching found nothing.

So I have a 99' XJ8 with the Nikasil engine with 120,000 Km on it right now. Shortly after the summer began, my timing chains threw codes for VVT bank 1 & 2. It was brought in immediately for repair, (No damage to engine apparent) the whole timing job was done by the Jaguar dealership. Invoice is below, (Simply to check if anything crucial was missed and should have been replaced)

TIMING SYSTEM invoice PAGE 1:




TIMING SYSTEM invoice PAGE 2:



I am the second owner, and there are 2 things that occurred to this car that would be worth noting before I go into powerloss detail.

1. The car did overheat, causing the thermostat and housing to melt, water pump was upgraded at the dealer. ( no complaints logged for another 10,000km)

2. original owner complained of vibration in steering wheel, (front end vibration). Two new front calipers installed, 4 new tires, rebalance and align on all wheels.
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Prior to the timing system beginning to fail, the vehicle could spin the rear tires and hand enormous acceleration, however vibration was still present.
The timing system with the old plastic tensioners would cause a huge vibration at speeds excess of 80kmph but only intermittently. In the time where a vibration was being caused the vehicle would have no pull, no power. This is when I brought it to the dealer.

after having the whole timing case replaced to the third generation tensioners, The car had plenty of power and pull, and only a small vibration in the front. (Assumed unbalanced tires)

after a few months of driving the vehicle, a small tapping noise could be heard coming from the engine bay... HOWEVER this noise is intermittent and is not always present.

Shortly after, the vehicle began to vibrate more and began losing power (same symptoms as timing tensioner failure) but it was intermittent. So back to the dealership I went. The dealership said there was nothing wrong with the engine although they did say it had lack of power and vibration?? They did not look into the matter further and sent me back on my way home ( 6hrs away!) Only 30 minutes into leaving the dealership the car went into failsafe mode on the 427 highway, and my car had no power steering, no engine, nothing.

Towed to the dealer… The dealer said the inertia switch turned on cause I hit “a bump” on the smoothest highway in Canada. They reset it, without charge due to me being furious.

Now I am at home, still having intermittent power loss and intermittent fill up issues (sometimes I can get a full tank in, sometimes I can’t get 1 litre in)
I get the following codes. P0442 (small leak detected) and P0455 (Gross leak/no flow) on the EVAP system. To lean on bank and 2 (intermittent) but this could be because of the cap I have sealed on the full load breather hole on the air duct, it is slightly cracked but shouldn’t be letting any air in.
The other day went I tried to make the car go, It misfired, bogged, and nearly stalled flashing a restricted performance light that went away shortly after. There is a raw gas smell on the side of the vehicle when running, and intermittently has a hard time starting (cranks but won fire) once it did it for a whole 5minutes. Finally it started.

I have no idea whats wrong with the car, I have replaced the MAFS, Checked the TB and breather tubes for cracks, as well as replaced the air filter and cleaned the part load breather because of oil in the air duct. I now have the full load breather bypassed (no more oil is coming out, but just in case). And regularly check the part load breather because when it gets dirty my engine uses litters of oil.

I’d like to mention that before the problem with the timing. The engine used ZERO oil.

Cleaning the part load breather seems to help the oil consumption, but im worried of NIKASIL failure now.

Also there is a tapping noise, and a whistle ( sounds like a vacuum) but they’re both intermittent and do not line up with powerloss issues.
The power loss can be described as a humming vibration deep in the engine, causing it to downshift once or twice to compensate. (When there is power loss the fuel economy shoots through the roof)
Hope you guys can help me thanks a lot!

 

Hi, sorry to hear that as a first post, but welcome!
The codes point to a good look into the fuel system from front to back, if it didn't post those codes then the induction system would have the unmetered leak, a more common issue.
I'd suggest you look for a good indie shop near you and get a leak down test performed on the engine, the last event sounds like a nikasil lining issue - I wonder if the dealer did this?

 

I will have a look at the fuel issue myself, im scared of the dealers as they wanted to replace my valve cover ( 900$ part ) just to clean the partload breather cause they say its the valve cover failing (Thats not the case) they just wanted money for the part.

but the powerloss is intermittent and so is the tapping noise. I thought maybe 3rd gen tensioner failure perhaps?

did you mean that the dealer caused the damages to the car, prompting the fuel issue and oil consumption?

 

I should have been clearer, I was wondering why the dealer didn't perform the leakdown test....

The ticking sounds like worn VVT solenoids and most on this forum go up an engine oil weight or add a can of 'Restore' to the oil to quieten down these units. Is the power loss linked to the clicking?

Its unlikely but not impossible for a tensioner failure, its not a hard job to remove the cam covers. My advice is to locate a cam cover second hand and re-fit the breather, blanking things isn't a good idea.

But before doing any of this, a leakdown test will show the state of the engine's liners, and from that point you can make a choice based on fact.