It refers to the trademark and by adding the word 'car' you have just made it more obvious which trademark it infringes on. Any development would likely be considered as 'passing off'. I would value this domain as *less* than $0 because an aggressive trademark holder can tie you up in court and cost you money. Not saying that will happen but why would you take the risk?
If it was me I would delete nameservers and let it drop.
Nothing. I would remove the nameservers - change any visible contact data and forget about it. Nobody's going to have a go if the domain doesn't do anything and they have to struggle to get in touch with you.