Bought my 97 Expy 2 days ago. 160,000 miles super clean, looks new. $3,900 from dealer. Drove it off the lot and hasn't run right since. Right when I got home, when I tried to start would run for a second then stall. Try to start again and nothing just cranked over and over. Luckily I have a neighbor that suggested trying the other key that came with it. Sure enough turned out to be the anti-theft chip in the one key, started fine since with the other key. Drove it to work today and 30 miles later has a miss. Hopefully I get this one figured out cuz I love the truck. Going to by a ODB2 code reader tomorrow.