Hi! First time posting. Don't know a whole lot about vehicles but I try to keep up. My 1998 Ford Explorer started misfiring a year or so ago. Very first code that was read was the mass airflow sensor I believe. Didn't worry about it, wasn't a bad misfire just here an there. Then it got worse and we changed the spark plugs and it went away for awhile. Then it came back and was bad, and it read that it was running lean and misfiring on 2 and 5. We did new spark plugs and wires again, changed the coil pack. Didn't fix it. Kept driving it (I know that's bad, but I had no other choice and no money to keep throwing in it) one day we put fuel injector cleaner in it and the misfire went away completely. For a day. Drove an hour away from home and had no issues all day, the next morning it misfired just like it was before. We also parked it for months after that because we got a new vehicle and we started it up one day and there was no misfire at all. Started driving it again for awhile and it started misfiring and got worse. CEL starts blinking too. So it's been parked ever since. It needs a new alternator now and a battery, and TRYING to figure out what to buy next to fix the misfire. I'm leaning towards fuel injectors because the fuel injector cleaner worked for a day.. But what do you all think? Fuel injectors, oxygen sensors, mass air flow sensor or what?

 

Do you know what engine is in your vehicle?

 

It's a 4.0 SOHC