I'm well aware cs that ABS is used in a lot of manufacturing components but most of these have had some R&D put into them as well as using ABS specifically used in these environments before. Lots of variants chemically in what actually makes up ABS.
As you would be offering these parts to others who then would put them in their cars it is only fair to point out a possible risk that may occur should the part fail especially as it is essentially untested. I say essentially untested because ideally you'd want a product before going on the market to be tested for a good length of time being exposed to as many as, if not all variants in temperature range & conditions.
I work in additive manufacturing currently as a Rapid Prototyping Technician so I use 3D printers on a daily basis although we use Projet & SLA machines which are a lot more high end than these extruding filament 3D printers.
The parts though even we create are for the most part intended as prototype parts for proof of concept/design, pieces of artwork, trial fitment parts, medical or for use in creating silicone tools which would then be used to create small run batch production parts using various types of resins.
Anyway I've said my piece and you know what you need to do if you do decide to go ahead with any type of batch manufacture.