Touring adds: Touring specific suspension Touring specific rear bumper (the black plastic part is different) 215/45R17 black alloy wheels with silver plastic inserts SofTex seats with blue stitching Blue accents around the side vents (vs. pearl black on the Four) Touring specific DRLs/parking lights (Four uses the amber indicators) LED Foglights LED clearance lights Prius Gen 4 Touring vs basic model headlight difference | PriusChat Post #16 and Post #18
Maybe worth noting: not 100% sure, but I think the non-Touring doesn't have fog lights, of any ilk. If their performance is similar to Gen 3, it's no great loss: it's nigh impossible to see any difference, turning them on/off. The do look nice though, better than matte-black blanking plate. IIRC, the 2016's had an oversight, speedometer could not switch units, ie: US Prius couldn't display km/hr. Toyota. And Toyota's solution was to provide owners with a card that explained the conversion... I'd second @bisco's mention of Exhaust Heat Recovery coolant leaks, 2016 for sure was known for it. Toyota provided a warranty extension, albeit time/miles limitted, is dragging their feet on replacement parts and not policing dealerships who (intentionally or not) neglect to make owners aware of the warranty extension. Dealerships are also prone to diagnose coolant loss as head gasket failure. Protracted neglect of the exhaust coolant leak can lead to head gasket failure, but the initial leak is usually not there.
Correct. No fogs from the factory on non-Touring - just that ugly black plastic blank. At least on the Prime, it looks like part of the design of the lower bumper. On the regular Prius, it does look like a plug. (Toyota did that with the Camry once but at least it was body-coloured and had some design by way of two or three lines across the cover instead of some nearly invisible dimples on the Prius)