There is a slight amount of stretch, but not enough to change metal/alloy properties of the bolt and it returns back to it’s original shape and is ready for for retorquing. The third example is a typical of an over-torqued bolt. Note that the bolt has not only stretched, but ...
it can clear stored error codes that may be causing the check engine light to stay on. This step can help diagnose any persistent or intermittent mechanical problems. Second, a reset can recalibrate the ECM to the default factory settings, which may improve performance...