1993 Toyota Tercel Shuttering and lights

I've got a 1993 Toyota Tercel, paid 500$ for it originally and never once had a problem with it until recently. Like all Toyota Tercels the car leaks some oil down into the spark plug tubes. Recently I put a custom cold air intake system on it which seemed to work fine, had to relocate some stuff, but that was just moving them around in the firewall cabin. Now as of recently, I was driving home and the car started to jerk, shutter, shake, acting like there was no fuel, yet when cold will start up and drive normal. I've thought and thought about everything, and don't wish to spend a limitless amount of money on something before knowing the cause. Has had a tune up, oil needs changed, etc. When the car goes to jerk and shutter it'll also die, sometimes starting is easy, the others it's impossible, lights kick on. Any ideas other than Fuel System?