Bad starter? I need to locate the starter on a 2000 Isuzu Trooper

The key lock cylinder operates the ignition switch sometimes ignition switch is separate sorry I didn't find where ignition switch is located if the lock cylinder is plugged into it.
You should have a starter relay and starter relay fuse.
This diagram of starter circuit shows the clutch pedal switch in the circuit on an automatic should have the neutral safety switch in the circuit. This is for 95 Rodeo.
Stater Motor Circuit Diagram (1995-1997 2.6L Isuzu Rodeo) (easyautodiagnostics.com)

How do I remove the key ignition cylinder? ' Isuzu SUV Forum (planetisuzoo.com)
Isuzu Trooper Ignition Switch Replacement ' Cost & Service ' RepairSmith
Changing the Ignition Lock: Changing the Ignition Lock, Safley ... (2carpros.com)
Starter and solenoid
Isuzu Trooper Starter replace under 1 Hour - YouTube
Isuzu Trooper (1995 - 1996) - fuse box diagram - Auto Genius
Starting System & Wiring Diagram - YouTube

This is for 2000 Trooper
Isuzu Trooper 3.5 L Starter Replacement - major time-saving tip!
https://www.youtube.com/watch?v=uajiKz6SFvQ

Crystal, this is what I found on the Rodeo starter fuse/relay.
Check the attached links,instruction and guides, Good luck
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1999 Isuzu Rodeo Main Fuse Box Diagram Circuit Wiring Diagrams
1998 Trooper Relay Solenoid Starter 1998 Isuzu Trooper All of

Are the battery an cables good ? Check the starter electrical circuit , voltage drop testing ! Why pull the starter , until you have to ! Starter Voltage Drop test the circuit before you pull the starter !

valve guide seals could be bad or rings could be getting worn or could need tune up

i have no a/c or heat in my trooper the fan would not cone on also

bottom rear of the engine at the transmission bell housing

the starter is located at the bottom rear of the engine, u access it from under the truck.

DOES YOUR TROOPER HAVE A 3.O DOHC TDI ENGINE IF SO WHAT GRADE OF OIL DID YOU USE

yes they have 2 cataletic convertors, one each bank
there is EGR codes, but only front O2 sensor codes and fuel trim codes no CAT codes
what were the scanner codes or flash codes i can work with both for helpful info
you can read codes by bridging pins 5 & 6 with ignition in on position engine not running