Ive got a 96 chevy silverado 1500. when i start it, it idles smooth for a moment, then the motor almost dies, and right before it dies, it rev's up real high. also, the truck rocks from side to side when you give it any gas at all. what is wrong with it?? could it be the throttle body?

 

it could be lots and lots of things by that descrption. have you checked for any major vaccum leaks? if you really are lost, see if you can post a video of what its doing ( post on youtube then link us to it).
just from you saying its revving really high i would start off by checking that the EGR isnt stuck open and make sure there are no vaccum leaks at all.

 

Agreed; check for any vacuum leaks and intake leaks, etc. I don't know for sure or not, but its possible that your PCV valve is acting up.

 

can you keep it running by giving it throttle?

 

hey man i know these two things are very much different
but i have a single cylinder nitro rc car, these engines are very small and run at 40k rpms on nitromethane
they have fuel lines and that is how you shut them off
you pinch the fuel line and it revs up real high and shuts off
you might be running lean, or have a clog in the fuel system
as for the rocking idk

 

but the difference is a 4 stroke shouldnt run rich enough to beginw ith to be able to rev up when it leans out like a 2 stroke
(on the off note plugging the exhaust is better to shut off the RC motor)

 

i know
i was just making a suggestion or link to the problem
and i dont plug the exhaust because it floods my engine