Let me tell you about it. It is a simplified, reasonably accurate version of a four-stroke engine, and it comes with its very own Haynes manual. It’s also entirely plastic and aimed at ages 10+. Bollocks, I say. If I had kids that age, I wouldn’t let them anywhere near the thing with their wickedly sharp craft knives. They’d have their fingers off before the first tea break.

The Haynes model internal combustion engine. Like Airfix, only not.

Let me back up a bit. A few months ago, I decided that I was going to learn about engines. I’ve always been a bit hazy on the theory behind internal combustion, and despite my father’s repeated attempts to explain, I’ve never really been able to get it straight in my head. This could have something to do with his insistence on explaining over the dinner table, rather than opening up the bonnet of his car and explaining there. (My brother got the lecture over the open bonnet of the car. He got so bored he fell asleep.)

This will all be a lot easier to grasp if I can actually do it myself. If I can take apart an engine and put it back together, you can be reasonably certain that I’ll know how it works afterwards. OK, maybe I’ll explode the back garden a couple of times, but I’ve accepted that as an inevitable consequence.

Miraculously, my new-found zeal is shared by a colleague of mine. She, too, wants to strip down an engine and see what makes it tick. Excellent! We ordered a plastic model to assemble in order to get a vague idea of what it will all involve, before thinking about taking things a little further. While we waited for the model to arrive, we may have become a little… unruly. Rowdy. Noisy. Obnoxious? Surely not!

After one of our exchanges, a colleague came up to me. She works in HR. You know the type: perfect hair, perfect nails, perfect smile. Was my enthusiasm too, er, enthusiastic?

“I just wanted to say, what you’re doing is fantastic,” she murmured quietly, and straightened the strand of pearls at her neck. “I love my car, I’d kill any fucker who so much as touched it. There’s nothing quite like a good engine purring, you know?”

I didn’t know, actually, but I nodded just the same.

The next day, another colleague was delivering some papers over my lunch hour when she saw the driving lessons website open in my browser. “Oh, are you learning to drive? Good for you! I learned in Nairobi, I thought I’d be quite frightened and sedate but it turned out I was a real girl racer, I nearly failed because I was speeding the entire time…”

I’m guessing that speeding will not be encouraged in London.

The next day, colleague Y came up to me, very upset, and drew me away from my desk. “I heard that you and colleague X are rebuilding an engine!” she said, looking very upset. Well, yes. Was this against her ethical beliefs? Was I in trouble with the ‘cycle to work’ initiative?

“Why didn’t you invite me?”

The thing is, I haven’t really mentioned this that much at work, despite being giddy with it for months. The people that have found out about it have either nodded sagely about how many times I’ll set myself on fire, or raved about how brilliant it all is. Invariably, my young female colleagues have fallen into the latter category. They’ve also taken the opportunity to ask me what I thought about the new Pagani (undecided, and I miss the Zonda R), the One-77 (I do like it, but why is it so angry? It looks like it’s been munching on stray pets) and plus, wouldn’t it be nice if the off-road vehicles didn’t kill your spine every time you went off road? (Seriously, Toyota, sort it out.) All of this was delivered in hushed tones over the tea and coffee, and by the time we were back at our desks we were very firmly back on either the Sudan referendum or the receptionist’s new hairstyle.

The Aston Martin One-77: Gratuitous car!porn. Image from CarzTune.com

Why? Was what we were talking about so shocking that it wasn’t fit for general consumption? Would the office spontaneously explode if it turned out that the female accountants and aid workers in my organisation actually knew their Nissans from their Nobles? Why did they get so embarrassed talking about it?

“Well,” colleague X said philosophically, “I didn’t get into cars before because I thought that it was a traditional male thing. And that didn’t mean that I couldn’t do it, but blokes would know more about it than me starting off, and I didn’t want to feel stupid. Then it turned out that they knew just as little as I did.”

Two hours later, a male colleague decided to ask condescendingly what kind of engine we’d be rebuilding. Would it be, he said, sneering, a rotating one?

“A Wankel rotary?” I asked. No. It would be a four-stroke.

• Look out for more Secret Diaries as Vik continues her engine adventure…