Engine covers: the mechanical equivalent of an appendix

Or how a “Monkey see monkey do” attitude results in millions being wasted in the car industry

When I was a kid, my father would take great pride in opening the bonnet of our car and explaining me the names and functions of all the engine components. We had a Volvo 142 from 1971 at the time so it was simple, straightforward but also hugely fascinating. All the components had their proper function and together they made sense….. and horsepower! Even the nec plus ultra of the engine enigma: the engine distributor would have no secrets to me.

And that was just a plain 4 cylinder!

Back then, every car enthusiast had a similar “look at my new car” ceremony. First you drooled outside the car (“look at those lines”), then you drooled inside the car (“Just smell the leather”) and finally the engine was fired up, the bonnet was opened and then there was the “drool over the engine” moment.

Done! Your passion shared like a boss.

Look at this, my child

Look at this, my child

And then, suddenly, someone decided that engines should have a cover, and everything became dark. Not 1 component any more in sight. I would not be able to explain the virtues of all engine components to my own son without making my hands dirty. Knowledge would be lost forever. It felt like a chain was broken… Overreacting? Moi? Naah!

Anyway, ever since I despise engine covers and now the time has come to finish them off!

You have to ask yourself: What is the function of this part and where did this polymer frenzy come from in the first place?

Somewhere in the mid nineties car journalists started commenting that the engine bay of some cars were “a bit of a mess”. Especially in comparison tests it became a common parameter to judge a car’s superiority compared to others. While I have sympathy for preferring a well thought through engine compartment instead of a spaghetti of wires, I hardly see this as a defining parameter when judging a car.

Whether this was the origin or not, around that time we saw engine bays being darkened by huge large pieces of black plastic. More worryingly, almost all manufacturers followed. Monkey see, monkey do?

So are aesthetics the main reason engine covers were developed?

You have to keep in mind that this is one expensive piece of plastic since it must be able withstand an enormous amount potential abuse. Not melt with red hot glowing exhausts manifolds trying to recreate hell a few centimetres below and not dissolve when chemicals in all colours and acid variations are being spilt in case of an accident. Anyway, all this results in one expensive piece of glass reinforced PP, even without putting a glowing badge on it. So just to hide some wires seams a meagre reason to spend so much money.

There must be another reason....Perhaps the engine cover is important for car lovers and mechanics?

Not in the slightest. They want to admire the components when all is well or be able to assess quickly what is wrong if not. Not to mention when you have a REAL engine in your car. All this plastic on top of 6, 8 and 12 cylinders…..that’s actually killing a sales argument, I say!

Look at my V6…euh….wankel engine……eu…4 cylinder?

Look at my V6…euh….wankel engine……eu…4 cylinder?

But perhaps it’s important for all the other people, those who are not that much into cars?

I really doubt it. Almost all people I know, with several of them owning nice cars, couldn’t care less about what’s under the bonnet. For them, opening the bonnet means evil, means trouble, means helplessness and could potentially lead to total humiliation when someone starts asking questions like “What does this thing do?”. Opening the bonnet for them is the mechanical equivalent of a spell. You are doomed!

So let’s summarize: it’s expensive. It’s not for car lovers. It’s not for non car lovers.

Think about it. We are all paying for an expensive component that has no value to us.…there must be something I’m missing here.



Or this?

Or this?

Wait, one last try! I can imagine noise insulation! After all, it’s a cover very close to the source of the engine noise. It results in a more silent car. Right? But if you think how far active noise cancellation techniques (ANC) have become, this argument can be countered by a much more efficient solution.

So there you have it. I give up. I do not have a clue.

Therefore my recommendation: Bury the thing. Kill it. Delete it. The car industry can save millions per year.

98% of the customers won’t notice and the other 2% will be happy.

win-win? Nope: Triple win!

Or what do you think?

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Comments (2)

  • Not always. Turns out the plastic engine cover on my Jetta is part of the intake.

      3 years ago
  • Perhaps the engine cover is hiding all the dark magic that happens beneath it?

      3 years ago