1st post, Learning XJs via YouTube and this forum, so Thanx for any wisdom up front! I would rate myself a 6/10 wrench who typically does not cut corners.

The Subject: ’00 Ltd, 160k, 0331 head, sat outside for 1.5yrs B4 me.

Completed to Date: Replaced IAC, TPS, CPS, CKS, plugs, coil pack, 4 hole injectors, couple oil/filter/Marvel/Seafoam, diff oil, battery, vacuum leak inspection to gas tank and back!

Appears to have had limited maintenance, running/most ticks have smoothed out after the work, still chasing a rough idle, slight lifter tick, and now hard starting more frequently. Oil pressure cold 60+, warm idling steady 35, warm driving 45-50. 200 degrees consistently. Always moist exhaust. Runs and drives great when off idle, plenty of power in all gears/drives. But the 750rpm rough idle is worse when in gear than not, tach needle bounces a little. Started to track coolant and estimate 1’ drop in reservoir over the last 175 miles.

Next I am thinking some vacuum checks and pull the VC to inspect valve train/pushrods/springs.

Does anyone see something I am missing or have any experience based advice?

Thanx again for the great posts and web site that is teaching me a lot!

 

Since you have the 0331 head, I would make sure your cooling system is in tip top shape. Might not be a bad idea to replace the thermostat (use mopar) and maybe even the pump. Completely flush the system etc. Any vehicle, but you really don't want that head overheating, they have a cracking problem. If you're loosing coolant and it's not on the ground, could be the head gasket. Pressure test the system and see if there is a small leak you aren't noticing.

The rough idle could be a dirt throttle body. Also replace plugs and wires.

Lifter tick is pretty normal on these engines.

Thats all I can think of at the moment.

 

good advice with the 0331 head. Definitely keep an eyeball on that. Honestly I would keep an eyeball out for a good replacement head when you can and cut it off at the pass before it has the chance to bite you in the butt. For some reason, almost all of them do for that specific year for the 0331 head.
Pressure test, you can rent/borrow the tool from most autoparts stores. The TB is quite easy to take off and clean.
the tick..yes.. but you can help limit the wear by using a good oil that is better formulated for our old school tractor I6's. A lot on here will use something like Rotella T6 diesel oil, as it seems to look after the parts better for the design. Some will argue with you on it, but if it can help and doesn't cost any more than the alternative, then I say why not?

 

There are no wires on the 00 and 01, just the coil pack that sits over the plugs.

x2 on checking the compression with the 0331 head.

 

There are no wires on the 00 and 01, just the coil pack that sits over the plugs.

x2 on checking the compression/coolant pressure with the 0331 head.

 

Thanx all, here are some more details!
Throttle body and IAC cleaned before IAC/TPS, switched out.
Compression check and vacuum checks coming soon! (Holidays in the way!!)
VC gasket on order, plan to check out valve train when that arrives also.
Replacing the fuel tank to vapor canister vent pipe right now just cause it is very corroded.
Not driving right now for fear of damaging engine.

 

Also, what TUPY heads are direct replacements and will accomodate the coil pack mounting?

 

Compression check (checked twice):
1 - 160
2 - 120
3 - 100
4 - 145
5 - 65
6 - 120

Idle vacuum jumping around between 8-13".......idle continues to deteriorate along with hard starting.
Valve cover is coming off tonight, hope there is something to see like a busted spring, bent pushrods, bent/stuck valve, or ???
ALSO....what motors will interchange with this 2000 4.0?