Lost 5th and reverse on my 97 nissan kingcab 4x4 four cylinder

5th and Reverse usually are on the same shift fork slider inside the manual trans. Fork may have become dislodged or shift linkage isn't engaging.

injectors
faulty turbo or internal crack
low cylinder compression
valve leakage
egr valve blocked or blanked off


also check ..
fuel pump pressure fuel filter
if hard starting cold ..glow plugs

Trans internal failure.

Here's a link ,check it out,may or not be it,is your Nissan a stick shift.If it's a stick shift,go check your clutch master cylinder's fluid.if low or empty,then your clutch slave cylinder is bad.here's a link on it.You can add fluid and bleed it for a temporary fix.

if it's a manual, the clutch is worn out. If it's an auto.....sounds like the shifter is playing up.

Check your ignition coils. I have an 04 maxima, and it shift very hard into reverse. Code p0174 is my problem. That’s the no. 1 cylinder being faulty (ignition coil no. 1). I’m changing my ignition coils in the next 2 days.

i would check the distributor cap for cracks, this can draw moisture when it rains, and cause a engine to do as you are saying, spit and sputter, and even cut out.

try the distubutor cap it may have a hair line crack when the engine get warms up it expands and trow off idle.

You don't provide much information to go on (type of vehicle, type of engine, 2wd or 4wd, etc.) RPM is always going to be based on the speed you're traveling with a standard transmission. My 4 cyl 5 speed Nissan pickup in 5th gear runs at 3000 RPM at about 75mph.

is there any pedal pressure when you step on the clutch? I had a similiar problem with my 91 300zx tt....it was stuck in third gear, no pedal pressure on the clutch whatsoever....i had cracked the pivot ball and the clutch slave 'popped out'. i had to pull the trans to fx the problem because i could not reattach the clutch fork onto the release bearing with the trans in the vehicle....you need to bleed the system...gravity bleed the slave until there are no air bubbles. make sure you top off the clutch master cylinder in the process.....then bleed the clutch operating cylinder.....it is in the passenger front hood near the power steering resivoir....top off the clutch master cylinder again. i hope this helps.