Chevrolet Repair: Chevy Cavalier Repair question, plastic soda bottle, cavalier repair

Question
I own a 95 Chevy Cavalier (automatic) and it has held up like a beast! Well, the car isn't working and I was hoping you would have any ideas or suggestions as to what to check.

When it quit working, I had just pulled into our driveway and i heard a "pop" like I had driven over a plastic soda bottle. I thought I heard it somewhere under the center of the car. The more I've thought about it...I thought it might have come from behind me. I didn't think much about it until my car didn't start again.

My husband and his semi-car savvy Navy buddies have been spending time looking at it. They have checked the catalytic converter...(from what they've told me). They have a fuel filter but have not replaced it. They changed the spark plugs right after it had happened..but that was before I told them about the "pop".

Any suggestions would help!

Thank you!
Kate

Answer
Hi Katie,

 This is a tough one to field but I might be able to shed some insight on the matter and help you narrow it down a bit further.

 If the fuel pump quit sometimes the injectors will spray a misty vapor of fuel into the intake and cause a lean missfire inside of the intake manifold.  It can be quite loud and make an audible pop.  What I would do at this point is:

  Take one of the old spark plugs and install one end in an ignition wire and the metal end clipped or resting firmly on the cylinder head making a good ground.  Have someone crank it and watch the gap for spark.  You should see a nice sharp blue arc over the electrode.  This will let you know if there is spark or not.  Do it on all four cylinders.
  Take an empty paper towel tube and take the gas cap off.  Place the tube down inside the filler neck and the other end to your ear. Make a tube long enough with cardboard or paper if you have to.  When the key is in the off position for at least 10 seconds have someone turn it to the run position (one before crank).  You will hear a 2 second buzz from the fuel pump if it is running.  The computer pulses the pump for two seconds to prime the fuel rail in order for it to start quickly.  I suggest not cranking it because it will be easier to hear the pump running.
  If you have no fuel pump sound make sure to test and check all of the fuses.  Not just the fuel pump one.  GM likes to double up and re-arrange fuse designations.  I have been caught on that before.

 Thats abouth te best I can do with the info you supplied.  Let me know if you need anything else.

Wayne Howie