Missing while driving/dying while idling on 1995 Nissan Maxima

I have a 95 maxima SE that I purchased 2 weeks ago. Both o2 sensors, EGR valve, new Bosch plugs, fuel filter, water temp sensor have all been replaced. No "check engine" light is on. Throttle body chamber is carbon free. I have had fuel injectors flushed, added Berryman's b12 to gas tank. I was advised by my mechanic that I had water in my gas tank and to add 1 quart of 70% alcohol to 1/2 tank of gas, I have done this twice to remove water, but my car is still missing BAD--, and dies when idling.. Please help

Asked by for the 1995 Nissan Maxima
Fuel quality should be easy to verify. Disconnect a fuel line and crank the engine until you get a two quarts of fuel into a clear container and allow it to sit. If water is present water will sink to the bottom of the container.
I had a problem with a wiring harness with broken wires in side the wiring harness on the passenger side of the engine compartment on two of these cars around this year. It set all kinds of codes.
Look also at the wiring harness all round the engine harness for wiring damage due to mice and rodents, seem them cause havoc on many occasions.
Your car has On Board Diagnostic 2 (OBD 2), using a scan tool to look at sensor values allowing you to look at sensor values without having to do intrusive testing.
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I know you aren't going to want to hear this, because changing plugs is a pain, but I put Bosch plugs in as a regular maintenance procedure and it started missing badly. I called a trusted mechanic and, over the phone, started to explain the problem. He interrupted me and said, "You didn't put Bosch plugs in it did you?" I said, "Why yes, how did you know?" He said, "Maxima's miss on Bosch plugs. Rip em out and put NGKs in and you'll be fine." I did as he instructed and the miss was gone.