This week on Car Talk, Tom and Ray help test a device that should strike fear in the hearts of all mechanics: a voice biometrics-based lie detector. Elsewhere, Corinne can't seem to get an oil change without a broken dipstick as a bonus; Christine's keys are stuck in her ignition--which may not be too worrisome, since her car won't start; and can struggling musician Dan fix his van's exhaust with guitar strings and an orange juice can? Also, a story that offers even more proof why you should never drive like Tommy! All this and more, this week on Car Talk.