Hi All, After several years of running nicely, my 1999 XJ8 Base 4.0L V8 engine died and now makes weird noise. Here is the history and a video of the noise. Anyone experienced this before?


HISTORY:

- Up until February 2014, car running great other than crusie control switch stuck in 'ON' position.

- February 2014, transmission 'Drum' failure. Had transmission re-built.

- Running fine for 1 month, then bank 2 OS (P1647 HO2S Bank B) heater produces MIL. Car still running smooth (OS working well when engine warmed up, but MIL remains)

- Car running smooth all the way through to October 2014.

- Oct 2014, Wife was driving car, stopped at trafic lights, and engine just died (no mechanical noises, or rough running, just died).

- Car towed home.

- P1647 still remains, pluse two additonal codes 'P0300 Random misfire detected' and 'P1313 Misfire rate catalyst damage A bank (1)'.

- Tried starting engine. Engine will not idle, and makes noise above 1500rpm (see video: ).

- Engine went into failsafe mode and would not fire at all (as expected in failsafe mode, everything shuts down).

- Eventually, failsafe mode goes away, but engine still makes noise above 1500rpm and will not idle.


DEC 2014 Start to investigate:

- Edit 12/27/2014: Forgot to mention brand new fully charged battery as a starting point.

- Bank A plug wells full of oil, Bank B plug wells dry.

- Dried Bank A Plug wells and coils. Engine still noisy and will not idle.

- Replaced All 8 spark plugs (NGK BKR5EIX-11 Iridium (replaces original manufacturers plugs NGK PFR5G-11E). Engine still noisy and will not idle.


Any thoughts before buying new coils? Wouldn't have thought this issue would be caused by coils though (i.e. more than one of them failing at the same time)?

Any thoughts on noise? I originally thought piston hitting valves, but a mechanic friend says the noise is unburnt fuel igniting in the intake manifold?

Initial thoughts are an ignition fault (stacks up with intake manifold noise)?

Could this be a fuel fault? (Fuel pressure reads 45psi at ignition on, drops to 40 psi after a couple of seconds, and is around 35psi when engine tryijng to run).

Could this be timing chain tensioner(s)? Haven't had covers off yet to take a look. Don't know if it has the original plastic tensioners yet?

Vehicle Details: 1999 Jaguar XJ8 4.0L V8

Regards,
Beaky.

 

It's not likely a fuel problem. If it were me, the first thing that I would do is to give the engine a compression check.

 

Beaky,

I have moved your thread from the forum for the X350 to the forum for the X308, which is the Jaguar factory code for your 1999 XJ8. Here you will find owners of similar cars who can offer assistance with your issues.

Cheers,

Don

 

See your problem. Have the tensioners and chains been done? Was there any front of engine rattle that went away after a 10/20 seconds?

Shows possible symptoms of having jumped a few teeth on the chains.

PS. Just went back and read your post again. You mention that as yet the tensioners haven't been inspected.Sorry.

 

First thing I'd do would be to test the battery. It's turning over really slowly.

Second thing : instead of throwing plugs and coils at it, why don't you fix the actual problem which is filling the plug homes with oil, ie faulty cam cover gaskets?

 

Since you have to take the cam covers off to take care of the oil in the well, the next step is very clear. Remove the covers and check the timing, then fix the seals if the timing is OK. Seldom is the next step so clear!

 

Thanks for the responses everyone.

Rickkk, I will check the compression in each cylinder.

Don B, thanks for moving thread to correct area.

Gippsland, I was also thinking the possibility of timing chain may have jumped, and need to check.

Mark SF, sorry, forgot to mention this really important step in the first part of the investigation. Started with a fresh brand new fully charged battery in the hope it was that. Still the same. Battery is sluggish in video, as it's been sat a few days and haven't charged it up again for the video. Now, back on charge.

Sparkenzap: Next steps, compression and tensioner checks and renew cam cover gaskets/seals over the next few days.

Regards,
Beaky.

 

I would not try to start the engine until you have looked at the tensioners.

 

+1

Have just done all the front,chains,guides,tensioners,w/pump,pullies and belt. Same ish motor,same mileage. Service history showed top tensioners had been replaced,true. I brought a kit to do the lot so replaced the replaced top too just so I knew.

Was very dismayed at what I found,plastic on guides was missing in many places (sump off to find the bits) and very sloppy chains,lower tensioners were shot. Not too hard to do. $1500 of our funny money inc post for everything.

So if you need just top tensioners I have an as new set you can have.Done less than 10k kilometres.

=Happy camper

 

A good battery should hold its charge for much longer than that, without needing charging. Something isn't right, with the battery, charging, or cabling.

 

Thanks Gippsland. Where did you buy the full kit from out of interest?

Hope I haven't bent any valves as well. Does anyone know if there's a way of checking for additional engine damage without removing the heads?

Thanks in advance.

Beaky.

 

beaky- once you know the camshafts are properly aligned a compression test should tell if you have bent valves.

 

Thanks. Time to start stripping it down to assess damage and parts needed :-)

Beaky.

 

If the secondary chain has jumped/snapped you still might NOT have bent valves.

I have replaced many chains/tensioners and quite a few times after a broken chain I found the exhaust cam had stopped in a 'closed-valve' position and NO VALVES WERE BENT. I bought my 1999 XJ8 for $500 because one of the secondary chains broke. The Jag dealer I used to work for did not want the car and neither did the customer. They called and I bought it. 2 days later the engine was running fine. All it needed was chains, guides and tensioners. (no bent valves)

Once I had a secondary chain wrap around the intake cam sprocket and pushed a large section of cylinder head towards the water pump. A new cylinder head needed to be fitted to the engine.

You won't know anything until you pull things apart for investigation. We can all guess about 'this-and-that' but we don't know!!!!!

Tell us what you find.

bob gauff

 

Cool, thanks for the feedback Bob. I'm pushing the car into my garage tonight, so I can start stripping it down to check the timing components. I'll comment further on what I find.

Regards,
Beaky.

 

Hi All,

Thanks for everyone's input. I've started with Bank-A, and the secondary chain has snapped as well as the secondary tensioner disintegrating :-( Next step is to start on bank-B, remove timing covers and replace timing components (and of course, start collecting all of the bits of plastic from head to sump).

Here's some photo's for others to see if interested.

Regards,
Beaky.

 

Bank-B looks ok, but will obviously replace the tensioner.

Beaky.

 

Man!....you have been pretty lucky so far.;o]
Your engine being an AJ27 model (solenoids sticking vertically out of cam covers) will have the second gen. tensioners which are still plastic.
The third and fourth gen. are the alloy bodied ones.

Judging by the colour of the cylinder heads, I would suggest this engine has not had oil changes too often and using poor quality oil which tends to exacerbate the problems with the tensioners and this design has a high loading
on the tensioners due to pretty radical cam phasing.

If this was my engine, I would be removing all four cams, remove plugs and do a compression test on each cylinder with a compressed air operated leak down tester...this should tell you whether any valves are bent without having to remove heads.
Or, you can do the same thing with a boroscope.

 

You can leave the intake cam in place to do a quick compression test.
The exhaust valves won't be opening but you should get a reading of 'more than ZERO'. The 'intact bank' is probably fine so I would not worry about that side for compression test.

Just remove the exhaust cam with the broken chain or visually look at the lifters to see if they have the correct lash.

If you see EXCESSIVE 'valve lash' then you will need to remove the head for repair.

bob gauff

 

Thanks xjay8 and motorcarman.

I've ordered a compressed air operated leak down tester, and will test when it arrives.

Beaky.