Hi All,
I tried to scout from Jaguar forums to find a similar noise than my XK8 (mod. 2000) engine is keeping but I couln't find exactly the same knocking & rattling! Here is a youtube link for a video clip which says it all. Any help would be highly appreciated please.
https://www.youtube.com/watch?v=7S_Y...ature=youtu.be

 

Jakke,

What about any DTCs from the OBD2 port? Any knock sensor codes?

Does the sound increase with engine Rev?

My first guess is the spark not being top of the piston stroke - pre-detonation . Bad gas maybe, bad knock sensors etc as computer should adjust the ignition timing.

Do you have a stethoscope? Listen to where the noise is coming from. Top or bottom of the engine?

 

You could try removing the serpentine and running the motor for a few seconds & see if the noise goes away.

It sounds like a rod knock to me or, possibly a dropped valve seat I'm afraid.

 

I had a similar noise from the chain ramp. Any timing chain work done recently?
Noise is not as sharp as I had from a valve seat dropping.

 

Hi David,
The car is still in USA and I'm hoping my broker will find the time during next week to take it into a dealer for trouble shooting. Keep you posted...

 

Hi,
According to seller, the time chain and tensioners has been changed. He didn't give me the receipts so I don't when or actually is this even true though?

 

My first thought is that the rev limiter is kicking in but I now wonder if the VVT is the problem.

 

Hi Gus,
What means VVT please?

 

VVT stands for Variable Valve Timing.

I asked a friend to look at the video and he suggested it sounded like a rod knock. I would suggest that it be looked at by an experienced mechanic.

In the good old days you could verify a rod knock and or a wrist pin knock by putting the car in gear and just bring the RPM’s up just a little and you would know however that is old school.

 

Hi All,
My broker took the car to workshop and here are the codes.

 

I tried to scout these codes (https://www.obd-codes.com/jaguar) but as for my understanding none of these codes are for "rod knock" per se, but it looks like it though?

 

Altough this says P0300 could be also "Worn camsaft" - will that fall in "rod knock" category? Sorry for my technical ignorance and language skills.

 

Well there you go restricted performance restricting the RPM to 3000rpm. I thought the car sounded okay at idle.

I would first ask them to clear all the codes restart the car and see what comes back.

The misfire of cylinders 1, 4 & 7. This could be oil in the spark plug well, a failed spark plug or a bad coil pack or your ECM needs repair. Oil in the cylinder and failed coil pack are the usual causes then the ECM. You can first take the easy steps by removing the coil pack cover and look and see if oil is in the plug well. If no oil then swap out the coil pack with one of the other coil packs and run another test and see if the cylinder misfires change to another cylinder. I would be reluctant to say it is the cam shaft just yet.

As for your for the other codes see what comes back after your second test.

 

Hi Gus,

You mentioned problems in spak plug, coil, ECM so can they cause this kind of engine knocking?

 

It is hard to trouble shoot without having my hands on it so I am doing my best at what is taking place.

Yes a misfire on one two or three cylinders will cause the engine to go into a restricted performance limiting the engine from going over 3000rpm. When that takes place the engine will seem to idle properly but when you force the engine to rev the computer along with cylinder misfiring it will begin to shake and pop and sound like something is broken.

Have them clear all the codes and see what comes back.

 

Any update?

Gus
JagRepair.com - Jaguar Repair Information Resource

 

Hi Gus,

Not yet unfortunately. I requested my broker to hanover the car to this workshop who read the error codes, maybe they can help? They didn't clear the codes though - I don't know why? I thought this goes without saying but it is a bit complicated to try to manage this from Scandinavia.