camshaft postion sensor

will my 93 cherokee throw a code for the camshaft postion sensor, i heard that the ecu will keep the last reading before the vehicle is shut off and then it won't start after that.

I don't think that's quite right, because when you replace the cam position sensor with a new one, the vehicle will start right up. I've had this happen with both a 93 and a 95. I'm not aware of any need to clear codes when a repair is made.

If in doubt, however, you can always disconnect the battery to clear the codes, and see what happens then. If the code was just a momentary glitch, it will start, and if it really is a bad sensor, it will not.

There's a trick with this vintage system, which can both get you home in a pinch and is also diagnostic for a bad cam position sensor. Turn the ignition on, leave it on, and then unplug and replug the sensor at the distributor. The engine will now start; though it may not run optimally, and may overheat owing to bad injection timing, you can drive it a few miles, at least. If each restart requires the same trick, you know the sensor is bad.

edited to add: the computer on these should hold a code for 40 restarts, unless you clear it.

i didn't mean clearing the codes, i've just checked everything and i have injector pulse and spark. i just think something not jiving right, it just won't run and im running out of options and about to take it to the dealership because pepboys refused it cause i have an ignition interlock device, i have a post up earlier about this but people stopped posting.