Three weeks ago, we ran a feature on cars that Autocar staffers like but perhaps shouldn’t. The phrase ‘guilty pleasure’ crept into the reasoning. But not for me.

In a motoring context, there’s no such thing as a guilty pleasure. Not unless it involves anything illegal or particularly immoral, and I doubt anyone could argue that liking the Rover Streetwise is either of those. There’s merely the pleasure. No guilt.

Thinking about this reminds me of Hagerty’s annual Festival of the Unexceptional (due to be held last week but cancelled for obvious reasons), a show celebrating cars that were the workhorses of their day.

It features cars such as the Austin Maestro and Nissan Bluebird. This is the kind of metal that’s described as a guilty pleasure for those who like and love them, whereas pouring the same amount of time and effort into, say, a Ferrari 250 SWB, isn’t thought of the same way. Average, common-in-their-day cars are perceived as less worthy of the attention and affection.

I don’t think they are. The proportion of rare and expensive classics that ends up cherished is high. There’s no peril for these cars. The mainstream stuff, which is a living museum for ordinary family life, deserves its place in history too.

So if you like a car, like it. And don’t think you ought to feel bad about it. Yes, even the Streetwise.

■ My guiltless pleasure is a ‘Baja’ 1970s Volkswagen Beetle, which has hit problems: a failure to run under load at higher revs. No, they don’t all do that, sir. At least not this badly.

It started after it had been sitting for quite a while. As with all things combustion, there are a few things it could be related to: air, fuel or spark. I think I know, but I’m hoping it isn’t that. So I started with the hopefuls.

It’s definitely getting enough air. I replaced the spark plugs and HT leads and checked the distributor, points gap and coil. I’ve replaced the old fuel lines, too (modern fuel wasn’t treating them too kindly), so I’m pretty confident that everything is fine right up to the carburettors.

Nice carbs, these: twin Dellortos. And I suspect that petrol hasn’t been kind to them, either, while the car has been sitting in a garage that’s not as dry as it could be.

Petrol today contains ethanol – up to 5% (E5) and soon up to 10% (E10). Ethanol is a solvent, hence the fuel line risk, and hygroscopic, meaning it absorbs water from the atmosphere. And that in turn can corrode metals – not just iron and steel but copper, tin, brass, zinc, whatever. (Zinc is used to galvanise steel because it corrodes first, protecting the steel it contacts).