Help me figure out my missing cylinder...

[Jeremy C]

Here's the quick and dirty of it"

My car has say neglected for 5.5 years. When I first got down here, I had some issues, and the car sat at a friends place for about 2 years. When I went to pick it up, pack rats had tore the under-hood insulation and piled tons of shit under the hood. After taking 30 minutes to wipe things out, I found very minor wire damage (no a single one chewed through, just some tape and a frayed wire. Replace the battery, throw in some clean gas, and she fires right right, but with a dead miss. I assume there's another wire I need to fix in the PTU area, drive the car to my place, and it sits unused for a while still. I start it and drive it around a little every couple weeks, but the alternator isn't charging so the trips are pretty short. Miss is still there, exhaust smells real strong of gas and afr's are consistently high (idles near 20). Now I'm trying to get my car road worthy again. Alternator is fixed (blew the fusible link being stupid, but it did it's job). 1/4 tank of fresh gas, and the car is running fairly decent. Still have the miss, though it's not dead like it was, but still pretty noticeable. I went digging into the harness and following wires expecting to find something broken... and find nothing wrong.

Here's where I sit: Problem is #1 cylinder. I pulled the plug and it's fouled. Swap it into #3 to see if the car runs better and it smooths out a little, but not what I want. I intend to get some new coppers and toss them in to see if that helps, but that doesn't explain the super rich condition and the high AFR. Now #1 was already weak before the long park, was hitting 185psi when all 5 other cylinders were almost dead on 210psi (10:1 motor). When I peaked into the cylinder the piston looked almost wet. What do you think the chances are that the injector stuck open, and would that cause the WB to see lean while pouring gas? I don't think a valve sticking would cause the issue, and I intend to pressure test again this weekend to make sure there isn't something else, but I keep thinking spark/fuel is the only issue.

TL;DR - WTF would go bad between injector/spark plug from sitting for 5 years?

[Hans@GZP]

swap injectors with another cylinder. It's easy since it's a front bank injector.

With old gas sitting in the tank, it can eat up the filter to the fuel pump. That debris can get sucked up, bypass the main fuel filter, and clog an injector. It could be making the #1 cylinder injector get low fuel pressure, which would cause it not to burn all of the fuel due to poor atomization.