My 91 integra b18a1 has about 165000 miles. Dropped the #3 intake valve. Not real bad.....the piston only has slight marks.... for some reason when it came loose, the piston smacked it just right to bend it and wedge it so it was stuck half way open. Luckily I was in the parking lot at work and not on the highway. I wasnt revving the dog #$%@ out of it. Along with the dropped intake valve on #3, somehow I spit the one of the #1 intake rockers and it was just sitting loose in the head. Is this pretty common? Let the beatings begin........I had some old gas I needed to get rid of and I figured that I would put it in the car and burn it instead of just dumping it out in the street. It was just a couple gallons and I thought it would mix in with the over 1/2 tank of good gas I already had in the car. This I believe was my downfall or maybe just coincidance. The car never started well afterwards and would pop-off and die a few times. Then it just cleared up and I could drive wherever. By the time I got to the end of the tank it was running poorly and ticking pretty loud. I guess what I need to do is check the other valves and see if they are sticking in the guides. Also check the springs to be sure they are not just worn out. Id hate to put a new valve in it just to drop another valve on a different cylinder..