The timing is off. it will need to be hooked up to a hand held computer system at a shop to correct this.
P0300 = random misfire.
Random cylinder misfire
Check the air filter.
u have to pull the whole distributer to change the pickup coil
the are identical go for it
a bad coil or plug to be safe change both
timing advanced, 180 out, Chevy requires delayed vacuum for advance, did you change the vacuum supply location? firing order 18436572 clockwise on distributer, turning distributer counterclock wise advances timing,
18436572 clockwise
change the fuel pressure regulator ,i had the same problem on my silverado 2000. that fixed the misfire.
This just happenned to me. I was getting a code PO300. It turned out to be the ignition control module. It cost 78.00 at autozone and only took 10 minutes to replace.
It's called a misfire... or random multiple misfire. It can be cause by a number of things. check your spark plugs for fouling, your spark wires for breaks or cracks in the rubber, your distributor, or your fuel injectors... it could be a tricky prob. or it could be easy as pie to fix...
Igniton System or Misfire