have a 2001 blazer started to run crappy now barely runs.ses light on came up with a po300 code [random missfire] replaced cap ,rotor,plugs,wires.still runs the same noticed when i pulled the plugs cylinders 2,6 were covered in gas while the rest were pretty normal.wondering if anyone has had this problem was told it might be the injector spider.dont want to replace it if i dont need to any suggestions would be appreciated.

 

Start with this thread:
The dreaded P0300 CAUTION LONG POST

There are a lot of suggestions and diagnostic checks to run through. Post up back in this thread if you need help or clarification on some of the steps.

 

this is going to seem like a stupid answer, but check to make sure that you put the spark plug cables back on in the correct order. I ran into this after replacing an intake gasket, accidentally traced the wrong wire, and spent considerable time trying to correct such an easy problem because i was sure that i had originally gotten the wires back on in the right spots. i know, i'm a moron. but it happens.

 

One other quick thing to check is that your wires are all the way on the terminals at the distributor cap. I have had more than a few cases of mysterious misfires caused by trapped air in the wire boot at the distributor. As the air warms up, it can push the boot off a bit, making for an intermittent connection. I always use dielectric grease in the boots before I put them on to keep the connection sealed. This makes this condition worse to a point. You must release the trapped air. An ice pick or small screw driver can be used to accomplish this. Put the tool of your choice into the spark plug boot part way. Then slide it over the terminal on the cap. Once it is fully seated, remove the tool. Done.