Car issue, need help ASAP

Sorry for the randomness of this, but it's 2am and it's been a LONG day.

I have a 2003 Pontiac Grand Am GT, 3400 engine, that sometimes starts, most of the time doesn't. We had an overheat issue due to a bad (intake or head) gasket back in August and stopped driving it. Since then we have replaced a few things. The mass airflow sensor is bad (unplugging while car runs should kill it, but it doesn't do anything). I was told that if that was the cause of it not starting that just unplugging it until it is replaced would let it start. After being stuck at work and making my wife come get me at 11pm with our 2 year old that had just fell asleep, I can assure you that is not the only cause. When we had the overheat, we had codes for misfire on cylinder 1, O2 sensor bank 1 sensor 1 overvoltage, and bank 1 sensor 2 low. We drained and refilled the coolant, replaced the thermostat and it was working. However, it would randomly not start, but we figured it was just the cold (-30+ windchills for a week) and would just wait until we got our taxes back and fix the gasket/etc when it was warmer.

We have not had the gasket fixed yet because it still doesn't start consistently. We had the Snapshot device from Progressive in when we were not using it and the battery died, so we replaced that. Since then we have replaced the fuel pressure regulator which that and the battery being 100% dead and out for a few days cleared the codes (was told a bad regulator is a common cause of those codes). But it still doesn't start all the time. Some days it starts and you can run errands all over and turn it off 5, 6, 7 times during the day with no issues. Other times it will not start at all. When it does start, there is no hesitation or problems at all, it starts right up. We are at a loss as the cause. The fuel pump runs when you turn the key, there are no lights on the dash when it does run, the air filter is a little dirty, but it was replaced about a month before we stopped using it so it's still good. We do not have anywhere near enough money to take it to a shop and tell them to figure it out because they will just start finding all these other issues and charge us for them when we can do those ourselves after we get it running. (drive belt, pulleys, harmonic, etc are starting to squeal and need to be replaced, and a small hairline crack in the top of the coolant surge tank but no coolant leak). My father in law does most of our repairs himself since he worked in a shop for countless years and currently works as a supervisor at Cummins. We don't really want to start tearing everything apart and replacing things just because they are starting to get to the end of their life, so any ideas?

{Admin please edit/move as needed}

Nobody has any ideas?

Sent from my Moto X to your screen via the magic of the internet.

When you turn the key on does the security light stay on or does it shut off like the rest of the dash lights do (Should) Starting with one thing at a time, the sometimes starts sometimes doesn't is an issue with pontiac grand prix, grand am, that has a possibility to be caused by the security system wired into the key switch. This basicly prevents the car from starting and will work sometimes and others not. Before you go replacing things, start with one thing and then after that is fixed (proved working) move on to the next. Has the ignition key switch ever been replaced or the radio ever taken out? As for the o2 sensor codes, it might very well have to do with the mass air flow sensor, but there are 2 other o2 sensors attached to the exhaust system (one before and one after the cat) I will do more research as to the codes, but if possible please post the exact codes that are being thrown. As for the cylinder 1 misfire this might be a coil pack starting to go bad, or the PCM going bad. I am far from being a master mechanic, but I have worked on a couple grand ams in my day. Buddy had a 2003 grand am that was having similar issues and it turned out it was the passlock system and the o2 sensor before the cat. He replaced the radio with an aftermarket system and it caused the passlock system to think the car was stolen and it cut power to the fuel pump and ignition system. Cycle the key a few times and wait 10 minuets and try again.

First things first, thanks! There are no more codes shown. After the battery was replaced there have been no codes shown. When it doesn't start, if I leave the key in the ON position, it shows this image Attachment 15503

When it does start, the lights are all off. I tried to read codes today when I took the picture, but there were no codes, it just said that the catalyst test and a couple other tests failed to complete, but I would imagine they wouldn't complete with it not starting. As far as the passlock system, from what I read, turn it to on and let it sit for between 10-20 minutes, or until the security indicator turns off. I tried that today, let it sit for 20-25 minutes with no change. I would have tried longer, but I was on my lunch break and had to get food before going back to work. The radio is still the original, never removed.

It seems to me like a somewhat large job to bypass the lock to test it, but here is a page I found that might help http://www.bergerweb.net/grandamsecurityfix.htm

When you left the system on did you wait 10 minuets and then turn the key off and then try to start? Or just leave the key on and then try to start?

When I drove the car to work on Friday, there were no lights on at all, just like every time it does start. That is why I never noticed the security light being on, if it didn't start, I turned the key back to off.