Nov 14, 2023
Okay, time for the new puzzler. This one will be a little better this time. This one is from a long time ago.
A while back, we used to have all these trade magazines in the garage. And just recently I was reading one of these old motor magazines and I was reminded of something that happened back in the garage back then that would make a great puzzler.
So, a customer came in with a 1985 Honda Accord. He wants a tune up. So we do the tune up. And after paying the bill, he leaves happy.
He comes back about a week or two later, saying, "Jeeze guys, I hate to complain but since the tune up, my car runs lousy first thing in the morning. Especially on cold mornings, and the colder it is, the worse it runs. I think maybe you all did something wrong."
So we all look at each other and do the mechanic shrug... So he leaves the car with us. And we just pour over it. We checked everything. We check the timing, we check the operation of the choke, and we can't find anything wrong with it at all.
So we give the car back. He drives it another week and then comes back and says, "Guys, I hate to say this, but it is not any better. In fact, now that the weather is getting even colder, it's even worse."
So we took the car back and parked it in the corner of the garage. Then one of my guys walked over to it and said, "Oh, I know what's wrong..."
Then, he replaced the air filter. Now, we had already replaced the air filter when we did the tune up. But he replaced it again.
Then he calls the guy and says, "Your car is all fixed." And he didn't even test it. And sure enough, the car was fixed.
So, here is the puzzler, how could replacing the air filter a second time have solved the issue? And I should mention, that the first air filter was not defective at all.
Good luck.
So, what was wrong? How did replacing a perfectly good air filter for the second time fix the problem?
And here it is.
The air filter we used in the tune up was brand new. But it was not a Honda air filter, specifically. It was an aftermarket air filter that normally would have worked just fine, most of the time.
However, in this particular Honda, this aftermarket air filter was too tall so that when the cover was put on, there was a space that you could only see if you stuck your head down in the engine compartment between the lid of the air filter and the body of the air filter, allowing cold air to sneak in and defeating the hot air induction system.
So modern cars at that time had a device that sucks hot air from the vicinity of the manifold. But when it's really cold it shuts out the cold air entirely and you get this pre-heated air going into the engine to combust the fuel.
But that couldn't happen in this case, because the air filter being too tall created a leak that defeated the hot air induction system.
I'm sure none of these issues happen these days, but in the 80's anything goes!
