Folks - new to board and I have an 01 Disco with a few miles on it and have a few questions that I searched but need some clarification. Sorry for the length - just want to get all the info out there

First off I do most of my own work on this beast but a few things have me stumped. Some history, truck is in good shape overall with lots of highway miles, all maintenance kept up to date but have some typical high mileage disco II related issues that I have been chasing and hoping to find some guidance here.

The sweet smell of coolant - multiple issues here. Replaced the aging jarvic heart (so brittle it essentially came apart when I touched it) That solved alot, easy and cheap. Throttle body de-icer - I have replaced once before with the updated kit lasted about 9 months...should I use some sealant on the next kit I get with the gasket? Still chasing an intermittent leak at the front - does not seem to be water pump. Will be tough to track until I get the TB done - any hints would be great.

Misfire on #3 - this has been around for about a year - comes and goes, truck idles butter smooth, great power, no issues. Just replaced plugs (oem champions) #3 looked like all the rest, dry and some carbon, not excessive. Wires (kingsborne 8mm). Truck seems to be even smoother after this (like hard to tell it is running when in the truck smooth) But still get misfire on #3. Coil packs - no idea how old or how long they have been in the truck - I got it with 60k - and I have never replaced, although I read they rarely fail...don't know on that one. I suspect excessive carbon build up on the valves as I have a a metallic knock on acceleration, usually all the time, faint and only when I push the truck but there. New OEM MAF about 2k ago - little better but not gone, same with plugs and wires, little better (knock wise) but not gone. So if I SeaFoam in the tank a couple bottles will that take care of the carbon or is it too excessive to budge at this point?

Whining on startup - not belt noise more high pitched psuedo metallic but tough because it sounds like a vacuum leak also a little bit. No pulleys' and have been replaced (thought about that) They all look "good" and smooth. Only happens when cold and the problem is only lasts for about 5 minutes after driving then goes away - only to resurface after completely cold again - also comes and goes.

Transfer case seepage - white shepard?

Overall the slight knocking has me concerned and the misfire but again truck runs great and has for the last 2-3 years with these issues so...?

Any suggestions? Thanks in advance.

 

Go get your coolant system pressure tested and fix the leak. I bypassed my t/body heater some just replace the seals. Make sure to bleed all the air from the coolant system after topping of the system
Are you still running the original factory grey wires, if so, get rid of them for some good 8 mm wires, if that doesn't help the misfire them do a compression test and or leak down to make sure you don't have a valve sticking.
Sounds like your SAI, secondary air bump noise at start up.
Yup white shepard on clean oil, consider a 75W/140 for the t/case and diffs.

 

Thanks for the quick response - couple of things. Installed brand new Kingsborne 8mm with OEM champion plugs. No SAI on my truck (01)

Planning to do the transfer case and diffs with the heavy weight oil.

My guess is coil packs rarely go bad? For the missfire? Seafoam? Will do compression and leakdown on that cyclinder.

Heard "bad" things about the bypass on the TB - I know everyone's experience is different - rather not bypass and repair correctly. I do drive in some low temps.