4.0 Inline 6 cylinder.
.035
The one and only 1.9 liter engine.
Best thing to do is but the universal coolant, it can be used in all vehicles.
Whats the fastest and most efficient
If it is a 4.3L engine the crank sensor would be located in front, close to the vibration damper on the passenger side. It is best accessed from underneath.
I believe the Chevy small block is the best bet for ease of change over and thecheapest.
Use the same spark plug that came in it, Champion for best results.
The hose going to the brake booster is a great place to test vacuum.
If its anything like my 2000 Wrangler, there's a switch on the floor just in front of the shifter. You just insert your ignition key into it and turn toward "off". Your best bet would be to check your manual though.
2004
Depends on the engine. If its the 4.2L the its a mechanical pump. It can be found on the passenger side of the engine block near the front. Best way to find it is to follow the fuel line from the carb to the pump.
If it is the 2.2 engine, on the lower passenger side of the engine block. It is best reached from underneath.