Actually if you read the link it is more about I cannot go to a trusted friend or independent repair person because any car mfg now days will not release their codes. In short no matter what make your car as it is going right now if it is new only where you bought it or the franchise is where they shut off the "IDIOT LIGHTS" why have they not forgooten the GPS display and given me a read out in their own way their presets for normal functions? Because only they are empowered to know this information. Not such a simple answer as a vapor lock...a seal on a gas cap in hot or cold weather has a +- of so much give it to me,, you cannot because you don't kjnow where that seal came from.