97 pontiac bonneville no start?

Sounds like you are experiencing the 3800 intake syndrome! What happens is the upper intake manifold cracks and it dumps antifreeze into the engine, causing it not to start. To check for this 1. Remove the throttle body assembly. 2. Inspect for a ruptured intake manifold at the Exhaust Gas Recirculation (EGR) passage. The passage will be located at the 6 o'clock position when looking into the plenum. It will be a hole approximately 5/8" in diameter at the throttle body mounting surface.

The car might have fuel and spark, but the fuel pressure might be too low. The most common cause for this is a plugged fuel filter or a weak fuel pump (which can be caused by a plugged fuel filter). And if the fuel pressure isn't high enough, it won't spray through the injectors properly, if at all, and would cause the random misfire code you got. Also, pull the vacuum line off of the fuel pressure regulator. If fuel comes out of the regulator, the diaphragm inside is ruptured and will require replacement.

So start by changing the fuel filter. If you get nothing, then you should next turn your key to the on position and see if you hear that quick hum that you should be familiar with... that is your fuel pump priming the fuel system with pressure. If you don't hear that, then chances are it is bad or there is a problem with the power feed to the pump.