Expert: Skip Bollinger - 1/2/2009

Question
my son has a 1996 cavalier LS w/2.2 For the last 6 months we have been having problems with it not firing, but the fuel pump is pumping. Change module, coil and crank sensor.
It ran for a month, it got cold and it wouldn;t fire the next morinng. later on that week it started and he drove it for a week and it did the same thing.  I change the cpu out and that didn't help. Is their anything that will let it fire sometime and will stop it again.  Thanks willie

Answer
Willie,
  If you read my "Profile", I'm a parts specialist, NOT a Tech but I will offer these thoughts for you consideration.
  In reading your mail, I will ask questions that you have left unanswered in the order that you asked them... Here we go..
1.  You say it is not firing. Do you mean it won't start OR it has NO fire at the spark plugs?
2.  You say the fuel pump is "pumping" but have you done a volume and pressure test?
Willie,
  I don't expect you to have all the "high dollar" diagnostic tools that are needed to check out these newer vehicles but I just thought I would ask.
  I have a degree in Automotive Technology. I do have some diagnostic savvy but I graduated in 1974. Because of my bad back, I went into the parts area of this business.
  From what you have told me, I would look for a poor connection (read corrosion) in a plug somewhere. My first look would be the coil connection, then the module connection, then the crank sensor and lastly the cam sensor. By this problem coming and going, I think your plugging and unplugging parts made the car run and then quit. Unplug every connector you can find and look for rust or green slime that may be causing a poor connection. You have replaced almost everything so it almost has to be a poor connection.  
  This is the best I can offer, brother. I hope it helps. Before you hammer my chops for being an idiot, again my Profile states I'm a Parts Specialist, NOT a Tech.
  Good luck.. Please have a SAFE 2009.
Skip