Probably one of the more pivotal moments in my life was when we went to the newsagents one Saturday in early 1983 (when I was 9) and rather than asking for Whizzer & Chips I spotted Car Magazine with the Porsche 944, Mitsubishi Station and Lotus Eclat Excel on the cover:

I persuaded him to buy me that, read it over and over, but only later in 1983 started to get more mags (at that time I was at a fee-paying school which included Saturday school so didn't get to go to the newsagents often). For some reason I started buying magazines monthly with What Car in November 1983; I filled in my 1983/84 back catalogue of Car from one of my stepfather's doctor colleagues who otherwise just donated his issues to the GP waiting room. Reading Car was amazing; it was pure chance that I stumbled upon probably the best era and best mag in the history of car journalism. That must have had a large influence on me as I changed from reading childish comics to grown-up magazines.
The thing is, my dad liked cars a bit less than he liked sailing so if it was just parental influence, I'd be a sailor not a car nut. I've been lucky to have had a wide variety of cars in my life from both my father's and stepfather's sides (and had a real comparison of my dad, mainly buying German, and my stepfather being more out there, buying things like a Citroen GSA and Renault 21). And their friends always had interesting stuff which I got to nose around; the GP mentioned above once turned up for dinner in a mk1 Golf GTI on ATS Cup wheels, later a Dimma-bodied 205 GTI and a Porsche 944.
Of course, I liked cars as a kid but was only able to help my father and stepfather choose theirs. But the knowledge from the 80s magazines came in very handy when I started to buy cars for myself after passing my driving test in 1990. Just wish I'd been a bit less hasty in buying my first car, a Metro from an old couple down the road. I had more interesting stuff after that; my shortlist for a ~£1000 car in 1996 when I lived in London was Scirocco, Audi 100 and Citroen BX GTI based purely on the old car magazine reviews, and I got as much fun then as any purchase I've made.