I could use a little help with an issue that came up. I was ridding on pavement coming back from a short ride, about a mile on a dirt road. I gave my ace some gas and when I stated to slow down the motor began running real rough and soon the motor died. I noticed the engine light came on. The motor would turn over and sounded like it would start but would just die again. I got the ace home and started checking it out. The owners manual says that the engine light comes on when there is a problem with the EFI. I first wanted to check to make sure my air filter didn't get dirty but it was clean. The one thing that I did notice is that when I cleaned the air filter the last time, which is at the end of every ride it seemed like I didn't have the air filter box lid on correctly. The two tabs at the bottom of the lid were not in the slots where they go which means that likely the air was flowing into the air box and then the engine with less restriction. As soon as I made sure the filter was clean I made sure the cover was on right. Then when I turned the key the engine started right up and the engine light went off. I've driven it close to home for about 15 miles trying to see if it would happen again and it's been fine. My question is, is there a sensor the would make the engine go in to some sort of safe mode and shut it down until the air filter box was sealed so that the right amount of air and fuel were mixing in the cylinder or was it just a coincidence that the engine light went off. I don't want to assume that it was just the air filter box not sealed and then get 10 miles out into the wilderness and find out it was the EFI.