I can understand your concern regarding vinegar residues leaching into car-care products when switching back&forth between these products.
(Vinegar can be use as a car-care product under certain circumstances.)
But as mentioned:
Not if plastic is washed, rinsed properly.
-But I'd be more concerned about the plastic containers chemical compositions leaching into either the Vinegar (household) or the (dedicated) car-care products.
(There are too many variables to state the exact time it takes for plastics to leach their toxins.)
As such:
There are no leach-free plastics on the market today!
To lessen the chemical exposure of "leaching plastics"...
I recommend checking the recycling symbol on the bottom of the plastic container.
(Note: Plastic products, including bottles/containers, sold in the USA must have these symbols)
Here are a couple of pretty comprehensive lists showing toxicity of plastics and their "amount" of leaching:
The least toxic with the least amount of leaching:
#2 HDPE (high density polyethylene)
#4 LDPE (low density polyethylene)
#5 PP (polypropylene)
Most toxic with the most amount of leaching:
#1 PETE (polyethylene terephthalate)***
#3 V (v-vinyl/polyvinyl)
#6 PS (polystyrene)
#7 PC (polycarbonate)
***The type of plastic bottle in which water is usually sold at stores is a #1, and is only recommended for one time use. Do not refill it. This is recommended because the older the #1 bottle, the more it leaches chemicals like Bisphenol A (BPA).
-BPA is an xenoestrogen, a known endocrine disruptor. Xenoestrogens disturb the hormonal messaging in our bodies. Synthetic xenoestrogens are linked to breast cancer and uterine cancer in women, decreased testosterone levels in men, and are particularly devastating to babies and young children. BPA has also been linked to insulin resistance and Type 2 Diabetes.
Very scary stuff!
Bob