1. A computer implemented method for providing a diagnosis for automotive engine malfunctions using collected vehicle emissions data, comprising the steps of: (a) generating a concentration level subset for each individual gas of a group of gases within said vehicle emissions data collected forming a plurality of concentration level subsets; (b) comparing each of said concentration level subsets with predetermined normative concentration break point value data sets to determine relative correspondence between each of said concentration level subsets and said predetermined normative concentration break point values; (c) generating relative correspondence data patterns representative of said relative correspondence between each of said concentration level subsets and said predetermined normative concentration break point values; and (d) comparing said relative correspondence data patterns with a plurality of predetermined relative correspondence data patterns for finding a match, wherein each said predetermined relative correspondence data patterns are each associated with a failure signature code, whereby said failure signature code is used to diagnose said engine malfunctions.