More trouble with my 1993 Buick Park Avenue. I just installed new spark plugs and ignition wires. Switched out the cheap copper plugs I initially bought for a nice platinum set. Found one of my new ignition wires was defective, returned it and got a new one. After that it stopped backfiring and smoking, but it still wouldn't run for more than two seconds at a time. It was making a loud "puff" type sound when it died and a friend suggested I look at emission systems. Seeing that a bad PCV valve could cause some issues I'd already had(rough idling, etc) and it was cheap, so I bought a new one and installed it. It no longer makes the "puffing" sound, but the engine still refuses to run for more than a couple of seconds. It sounds like it might be getting a poor fuel supply? I really don't know. I can keep it running for a bit longer if push the throttle, but it invariably cuts out after a while.
I'm still reading around and trying to build my knowledge, hoping I might figure this out somehow. Unfortunately, that noise was my only lead and it's gone now. I can't figure out what else could have changed here. Really, any help, even a push in the right direction would be greatly appreciated. Thank you very much for your time!