I have a 2000 blazer lt 4.3l. It has a p0300 random cylinder missfire detected. It also has a p0507 idle control system revolutions per minute higher than expected. The cap rotor wires and plugs were new. I replaced the ignition coil and it didn't resolve the problem. It seems to not really missfire under acceleration as much as it does at idle. I got the truck from a buddy with some kind of a used car license and the truck is from an auction. By law he can not transfer ownership of it until it passes NYS inspection. I really need this on the road. Im a single dad trying to support a 7yr old and cannot afford a shop. Can anyone please help?

 

Do a search there seems to be allot of these issues