2001 XJ8 - 77K miles, picked up cheap knowing it needed work. Started with multiple misfires codes here's what's been done so far.

NEW
2 new upsteam O2 sensors
8 new plugs
fuel pump
fuel filter
air filter
timing chains, guides and tensioners (all)
water pump
belts and hoses
fuel injectors cleaned


Got all my misfire codes down to a single cylinder #4, had car towed and a professional Jag tech do compression test and check all my work. Compression in all cylinders were within range 170-190 except (you guessed it) no compression in cylinder 4. Sent a camera down the plug hole and picked up something (valve or spring). Car is now back home and I'm about to set out pulling the head off - (of course wishing I was smart and experienced enough to have done this when I did tensioners and chains. A few questions for the experts out there:


1.) any good step by step instructions on removing the head... I know many steps are the same as when I did the timing chains/tensioners.
2.) Hoping it's no more than a broken valve and a machine shop can rebuild - what else do I need to be checking for with regard to piston and ring damage once the head is off.


thanks
jamie

 

Pull the head and you will know everything you need to know. My guess is:

If there is something loose in the combustion chamber, it could be a bad day, hopefully it is just a bent valve. If it is a dropped seat, you may be looking at a replacement engine for various reasons.

Keep us posted as to what you find in there.