So long story short, life happened and I wasn't able to drive my RX-7 for about two years. It's been sitting in my garage the entire time, but I didn't do any sort of storage maintenance on it. It needs a new battery and I need to get the old fuel out, also planning on an oil change that was coming due. What else should I do/did I do by letting it sit this long?

'94 with 70k miles on original motor and turbos. Always had a clean bill of health before this.

 

IMO, it shouldn't be too bad. Replace the coolant and gasoline and you should be good to go. Something else may show up that needs attention, but with a 30+ YO car, that will always be the case.

 

Is coolant a must before driving or just something that should be made a priority?

 

Made a priority. Install a new OEM JDM thermostat (Not the Mazda USA Stat) and consider replacing the coolant and heater hoses if you haven't done that yet.

 

Convert to Evan's coolant if you plan on letting it sit like that every again or even if you plan on keeping the car for a long time and don't want to keep replacing coolant every few years, its lifetime coolant, never have to worry about rot like you do with water based coolant. I don't ever want to deal with rotted out irons.

 

i'd start it and make sure it runs ok, then change it later

 

Before running it hard, I would also do a preventative cleaning of the fuel system once you run the tank down to like 1/4 or an 1/8th. I use B.G. 44k and dump a can in when its really low on fuel, take it for a drive around the block, no need to go far. You just want it mixed up and a high concentration in the system making sure it reaches the injectors. Then let it sit overnight or over a few days with the high concentration in the injectors and the rest of the fuel system. This will help break down any gelling that may have happened if you have ethanol content in your fuel like 99% of fuel does. I wouldn't run the car hard until you do this, all it takes is one sticky or partially plugged injector to trigger a rebuild.