96 No Start

I have a 96 Roadmaster and am stumped. About 2 weeks ago went thru some snow slop and then it was missfiring. that cleared up after 10 miles. I am sure I got my Optispark wet. 3 days after that it wouldnt start. Felt like no fuel pressure. 2 hours later it fired right up and ran fine. Next day started up fine. went to work, car sat for about 1 hour, started fine. Went home. Car sat 5 min would not start. Again seems like no fuel. Put on fuel gauge and no pressure. Checked 1 hour later and now have full pressure (40ish pounds) Now car starts and runs for about 3 seconds and shuts off. Pressure gauge shows fuel pressure fine. Fires right up again and shuts off after 3 seconds. Have tried this about a dozen times. I disconnected the battery for 45 minutes to possibly restart the computer however this did not change anything. Again runs for 3 seconds. Is there a sensor to look for that will tell the car to shut off? I dont even know where to start looking.

welcome to AF. Start by checking for spark, no? Then get as noid lite on the injectors and check for pulse.

it starts and runs great for that 3 seconds then it just shuts off. wouldnt think it would be a spark issue

Is the security light flashing when trying to start?

This weekend I figured out what was the matter and I thought that I would post it here because I didnt see this answer on any of the other posts. I ended up taking the big triangle part (I think called a sound box?) off of the engine so I could get to the gas pressure fitting and the fuel injectors. This opened the 4"? hole that went to this box. This caused the engine to get the air in here instead of in front of the mass sensor and such. As usual most repairs that I seem to have to do are usually due to my own doing. I want to thank you for your advice and for the smart people on this forum. I use it quite often to keep all of my cars as well as a large stable of my kids cars (which always seem to be breaking down) on the road. Happy holidays to all. Rodger (99vetteman)