The facts of Susan communicating to the gas station that she was having car problems and the observations of the mechanic discussing problems with the petcock plug of the radiator, that would suggest that someone was intentionally sabotaging Susan’s car to make it overheat and cause her to pull over. This would coincide with the mystery suspect and car arriving at the gas station while Susan was having car problems in the middle of a blizzard.
The description of the suspect vehicle being a “muscle car” with mag wheels, in combination with knowledge on how to cause Susan’s car to overheat, would suggest the suspect was a gearhead.
It’s likely he would be known in the area and there might have been other girls approached, followed or had communication from someone matching this description and car. We need to make sure this case gets with people who might have been around in this part of Minnesota in 1988!
Some reports online make note of Susan and a “mini-skirt” she was changing into. Here is a picture of the actual skirt Susan would have been wearing and is not consistent with what most people may be thinking of when they see “mini-skirt”. Just FYI, when reading through case details.
I also believe that someone (either at the gas station or someone had been watching Susan since she arrived at the mall, tampered with her vehicle while she was working, then followed her to the point she realized it was no longer safe to drive and pulled over) intentionally disabled Susan’s vehicle and then offered her a ride when they were given the perfect opportunity (late at night during a snow storm and she was alone & vulnerable). The location of the gas station is a lot closer to her home than the mall, this makes me question if someone stalked her the entire way from her work to the station.