For the past year my 95 5.slow has been running like a champ. Decided to take it for a joy ride last night. It started out OK; I noticed a slight miss at idle, but over the years my car's done that from time to time when it's sat for a while so I didn't think much of it.

Anyway, as the car got warm, the "miss" got worse and it started to "stumble" and hesitate a bit at lower RPMs. Once past 2000, it seemed to pull normal. I decided to head for home. Heading up a hill close to home, the car would NOT rev past 1000 RPMs and was bucking/shaking badly. The check engine light came on. I barely made it up the hill. I finally got it home, where it stalled in my driveway just in front of the garage. I started it up to try to pull into the garage, and it was very, very "choppy" at idle (sounded like I had a big solid lifter cam or something) and lots of black/gray smoke was coming from the exhaust.

I shut it down and popped the hood to see if anything looked out of place- my air filter had somehow fallen off of my cold air intake. I put it back on. I checked everything else out and everything seemed OK. I fired the car back up and got it into the garage- seemed OK.

I haven't had time to take it out (and with the rain tonight, I probably won't). It is idling OK now. I checked vacuum and spark and they're normal. Fuel pressure is reading normal as well.

Could an air filter off cause major issues? I wouldn't have expected it to (since the MAF and IAT were in place normally with no air entering beyond either). Could my air filter being off have caused my problems?

Feedback appreciated.