97 jeep Cherokee sport no start turns over but no spark on fuel an no gages work what could it be already changed crank sensor

I looked at info for 4.0L engine. I don't know what testing you have done?
make sure battery has a full charge, if it cranks good but won't start, have a helper crank it while you visually check for spark at the spark plugs. If spark everywhere, use a gage and check proper fuel pressure, also, check fuel injector pulse. If your missing all three, check cam and crank sensor. Don't replace anything unless your testing points in that direction.
Any applicable trouble codes? What about security system?

Bill, No known inertia switch for your vehicle unless installed aftermarket. Could be Cam or crank sensor,security issue,etc., have a good tech. scan for trouble codes, diagnose and estimate repair. Check the attached links,instruction and guides, Good luck
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97 Jeep Grand Cherokee cranks won start no spark or fuel Forums
How to Troubleshoot No Start Condition Jeep 4 0L
So your engine cranks but wont start

U need to check the crankshaft position sensor. The fuel pump will only have power for 2 seconds I till it sees a crank signal. It' controls the asd relay which turns on your spark and fuel

crank shaft sensor just had this prob its located on top of trans

In a 96 Jeep not many sensors are involved. Basically Fuel and spark delivery at right time should start car if your Starter is able to crank the Engine.
If engine is cranking then the battery is Okay. Check Spark directly at the spark plugs and fuel pressure at the fuel rail. You may pull out one spark plug and check spark out of engine.
Try spraying Starting fluid in Air Intake while cranking. If Jeep starts then not enough fuel is being delivered by fuel pump. If you find no spark at plugs then check circuit for starter relay, Crank sensor/cam sensor problems.
A kill switch or bad Alarm system can also cause this problem.
Here is the Elec Diagram:
http://www.alldatapro.com/alldata/PRO~V451756054~C28087~R0~OB0~P4R0H~N/0/41746574/56418469/56418476/56418477/34853741/34864081/56251052/56251070/55276088/76721401/58958330/57479434

I’m happy to assist further over the phone at https://www.6ya.com/expert/uttamjeet_2f3adc18600f8ede

you need to have it connected to an OBD2 machine and watch if you are missing the cam sensor showing RPMs
or if your missing crank sensors RPMs,
it could be a wiring problem or computer if your seeing the RPMs from both sensors,and the last thing i would check is hooking up a fuel gauge to the reed valve and watch what fuel pressure you have while cranking,if the cam sensor is the culprit it will turn the fuel off after the cranking.

take a spark plug wire off and hold it near a metal object on the engine 1/2" and see if you see spark jump if so, its good, if it has spark, take some carb cleaner and shoot a short spray down the throttle body if it starts, then its a fuel problem. Ck the reference voltage, it should be 5 volts if not there is a sensor shorted.

you need to see if you have spark and check all fuses and see if you have fuel pressure and injector pulse if no spark and no injector pulse suspect crank sensor or ignition control module if no fuel pressure check fuses then relays and then suspect pump

Seems to be a chronic problem with crank position sensors... On yours it is tested between b&c terminals and should have no continuity there. (should show an open circuit if good)

check the fuel pump fuse/relay, could be just bad enough to cause an intermittent start/no start. and check fuel pressure,spark and the crank position sensor.