Have a 2003 Ford F150 that started missing and as usual the Haynes Manual is about as useful as a sack of marbles on the steps of Angkor Watt. Ordered this code reader and got two messages; both saying in effct that the number three cylinder is missing. Odered a replacement coil from Summit and with a minimum of grimy knuckles the beast is purring like a kitten. I like this tool... but electronic ignition systems will never be as reliable as 1950s technology. Detroit is making it harder and more expensive to do simple home repair. Good tool, bad auto-motive design! Baaaaad!