For the past month my '96 CE with LT1 has been running rough when cold and also doing more popping during deceleration than usual. Just yesterday the roughness increased dramatically to the point that the car would hardly run until warmed up. I also noticed it was nearly backfiring and eventually threw a P0300 code. I did some research here and found that the P0300 code (Random/Multiple Cylinder Misfire) can be any number of problems which left me nervous because some have become very frustrated chasing this down. I went under the hood and started looking around for anything obviously wrong. Lucky day for me because I found that the PCV hose on the passenger side valve cover had worked itself loose from the valve cover fitting. There was a fair amount of oil residue on the valve cover itself as well. I carefully cleaned and then reattached the hose and took a test drive. Now the engine runs smooth with no popping while decelerating and the P0300 code has not returned. Drove to work this morning and it still is running great!

Just thought I'd share this story because many have struggled with this code and this can be one example of a potential fix that cost me nothing. Just one more thing to check if you have the P0300 code and the sysmptoms I had.

 

 

 

That plastic PCV tube sucks. I drove around with mine loose for the longest time, because it had heat-warped so much that it wouldn't plug in anymore. Finally I bought a new one for 10 bucks or so.