well i put a new alternator on but its not charging, i brought the truck up to advance auto parts where i bought the alternator and had them test it on the truck and it was putting out nothning, ik think it is something other than the alternator not allowing the alternator to turn on, so im gonna take the new alternator back off and have them test it off the truck, what do you guys think

i doubt this has anything to do with it but my overdrive is not working
i bought the truck with these problems, it had been sitting in a field

 

I think the pcm controls the charging and OD on the 92-93's, not but I'm not100% sure.

 

over drive=tps?
charging=crank shaft postion sencer
for things to check

 

how do i check these things? im learning this stuff, and im on a budget

 

since you got it out of the feild, does it even have the tps and look in the sticky on how to adjust it.
crank shaft position sencer look above the crank to see if its even there and check all the connections from your alt to the batt and so on.

 

the tps is there and i played with the plug a couple of days ago with no luck. just looked at the truck and the crank sensor is there

 

i was thinking it might have a bad conection,
does it shift into over drive at all and does the speedo work? check the wires from the speed senser too.
for the alt i don't know other than coonections or just a bad one or voltage regulater which i think is in the pcm, but not sure.

 

no it does not shift into overdrive at all
yes the speedo works

well i gues about the only other info i have is that i put a test light on the positive post on the alt. and have continuity

 

i'm out of ideas then some one will help who has had this problem.

 

i hope so!

 

Check the wiring to the crank sensor, it is notorious for shorting out or breaking, especially where it comes around the front of the head.

The fact that the OD does not work makes me really think the crank sensor or its wiring is the problem. The PCM does not know the engine is running if there is no signal from the crank sensor, so it will not turn on the alternator, A/C, or OD.