I have a 96 Blazer 4.3 with 142,500 miles that has a starting issue in the past 6 months. At least every other time I go to start, it does one of the following. It either starts right up or it takes a few seconds to start. It also makes a loud screeching grinding noise almost every time I start it up. I checked the voltage and everything seems to be running fine. What could this possibly be? A faulty fuel pump, serpentine belt??? I would like a few suggestions before I start tearing into things. At first I thought it was the starter, but like I said it does it randomly. Some times it starts right up with no noise or anything. Here is a video of the noise. Note: The truck was already warmed up when I recorded it.

Blazer start - YouTube

 

had kinda the same problem on my silverado, check the wires to the starter and make sure there on tight if that means unbolting an putting back on try that, if that dont work, you can also check your distrubiter cap an make sure thats not cracked or anything. if none of those work let know