okay someone must of had this problem before. 98 blazer 4wheel auto . when i accelerate hard and rpms get to amout 4500 the engine surges and the voltage regulator cycles on and off rapidly . 14.5 volts then to 10 and back. i have never had a altornator do this. i changed the belt last night to no avail. tensioner feels okay. is it the altornator or is the computer shutting off the regulator for some reason . cam sensor, crank sensor ? check engine light is not on and at idile with everything on gauge reads 14.5 volts. i know the proscess for troubleshooting this just am looking for a similar experience with a solution
thanks

 

at what speed besides 4500 RPM`s does the truck do it?