howdy! im new to this forum stuff so please be patient with me!
i have a 1992 Chevy Blazer 6 Cylinders 4.3L CPI.
when i first got this truck 6months ago i had zero problems, here recently the idle on the truck would be at 2000rpms and stay there while in park, and when i placed it in drive, the truck would jump and accelerate on its own.
the fastest it has gone is 33mph!! keep in mind im not pressing on the gas.

also yesterday it has started to not start after i drive it for 30mins, i have to let it cool down for it to start up again.

things i have replaced-fuel filter, air filter, bleeder hose, spark plugs, wiring for spark plugs, cleaned distributor, tested ICM at autozone and it passed, brand new IAC valve

any help would be greatly appreciated! i know this problem is probably a simple one!
thanks