The guy behind the counter said "plazteewhut?" when I recently dropped in looking for some green Plastigage (aka Plastigauge) and assembly lube. His more senior-looking associate said they hadn't stocked it for years, and that I should try the import place down the street. That man knew what Plastigage was, and even seemed impressed someone in town was asking for it. I made two more unsuccessful stops before landing in a NAPA store that not only had Plastigage, but whose salesperson knew enough to ask which color I needed.

Since I live in California -- a locale purportedly in tune with the automobile -- and Plastigage awareness isn't what I thought, perhaps I should explain. Plastigage is essentially a plastic thread with which you verify bearing clearances and find out-of-round or tapers by placing the thread between two parts, torquing them together, then reversing the process to see how much the thread has spread apart. Using the gradations on the sleeve it comes in gives you a good indication if your machinist (or his tools) are dialed in, or that you got the right size crank, bearings, piston pins, or whatever. It isn't a substitute for improper machining, just cheap and easy insurance for putting any precision assembly together.

At the third store, I was beginning to think no one gets dirty any more. I know modern machinery can often as not be fixed with a fuse or re-flash or by disconnecting the battery for a couple minutes, and that changing oil or brake pads can be a messy proposition. But I've apparently stumbled onto a generation, or social stratum, oblivious to how much fun it is to scrape knuckles and get grime under your fingernails: those who don't know the delight of dirt.

It doesn't matter how cheap or exotic the machinery is. When you show a freshly licensed teenager the margin between a crankshaft and a main bearing, and then pour cold motor oil in front of him, the smart ones immediately get a clue as to why you don't rev stone-cold engines. Move the piston up and down in the cylinder and ask if he can comprehend that happening 100 times in one second, and if he realizes piston travel in feet per mile could be a stat worth knowing. And if your motor's advanced enough -- our project is a V-6 from a 20-year-old SUV sold around the world -- the kid might learn what cross-bolted or six-bolt mains look like. To me, this is more relevant than how one ladder-frame all-wheel-drive SUV is accelerating faster at 90 mph than a competitor might be.

Besides learning things about engines -- and I'm still learning a lot with this latest project -- rebuilding stuff with friends is often good entertainment. How many of you have put together an engine only to later find one small part that rolled under the toolbox? (My hand's raised.) Then your buddy says, "I thought you put it in," and you reply, "You said you put it in." Then his wife, sensing something awry despite the laughter, but clueless as to what we're talking about, says, "I told you it was a bad idea to put the beer fridge in the garage."

Then the Los Angeles auto show beckoned, and I had to clean my fingernails and bandage the ugly knuckles, as bloodied concept cars are bad P.R. But I should have left my knuckles ugly. Following the Mazda CX-5 introduction, there were so many Kia/Hyundai engineers swarming the vehicle, I had to shove them out of the way to complete my assignment.

After too many more unnecessarily loud press conferences, each taking at least twice the time needed, attended by too many people who shouldn't have been there, I made it to Chevrolet's presser in not the best of moods.

Like good cinema marketing, the silent movie trailer began. Cars, trucks, and traffic: lines of slow-moving vans and crossovers slithering askew in a blizzard; shimmering waves of hot air wafting off idling city traffic; long sunset shadows from freeway gridlock that resembled Cubist art.

Why was I watching this depressing film? Was Chevrolet implying it could undo the damage from 100 years of building vehicles or a hundred million small-block V-8s by introducing one subcompact car and pointing out that Jay Leno's done 10,000 miles in his Volt gasoline-free?

They showed the Spark in its U.S. trim with 85 horsepower and 43 mpg, then countered with a Camaro ZL-1 at 580 horsepower and mileage unrevealed. And before it all, a feel-good story about a father's 1965 Impala coupe sold decades ago, how it was tracked down and acquired by his sons, and the subsequent father-Impala reunion captured in HD video. I was hoping there'd be some father-son restoration aspect, maybe a dirty-hands story about how they freshened the small block at least, but alas, it was not to be.

A few more conferences and two receptions later, I left.

I hopped in my bulletproof, efficient modern car, drove home, changed, and went back out to the garage. One deep breath to remind myself there's more to cars than shiny paint and the smell of synthetic leather, and I got dirty.