Mass airflow

December 16th, 2006 1 comment

Back out of the driveway. Hit the garage door opener. Shift into first. Smoothly let out the clutch and slowly roll on the gas. Clutch. Into second. Clutch. Gas. Wait a few seconds… punch it! “Growl!” goes the engine. “Whoosh!” flies by the world. “Grin!” goes the face. The Bimmer is back.

After fighting a mysterious intermittent check-engine light for the last year, I finally won the battle. The problem turned out to be a degraded mass airflow sensor (MAF). The MAF measures the amount of air that is coming into the engine, and the engine’s computer uses that information to decide how much fuel to inject, among other things. Besides the annoying dash light, the faulty MAF was causing a serious loss of power between 3500 and 5000 RPM, which I had chalked up to bad spark plugs — until I changed the plugs and the problem remained.

A five-minute session in the garage was all it took to swap in a new MAF. I must admit to cheating a bit on the replacement. The genuine BMW replacement MAF is about $400, and that’s just insane for what is essentially a piece of plastic with a wire running through it. Fortunately, the BMW MAF is actually made by Bosch, and that particular model is used in a number of other cars. One of the other cars happens to be the Volkswagen Jetta MK4 VR6. With that information, I went to the VW dealer and exchanged about $100 for a VW-branded Bosch MAF. One hundred dollars is still outrageous, but it’s better than four hundred dollars.

After popping in the new MAF, I backed out of the garage as described in the opening. Excuse the vulgarity, but damn that car pulls hard now. It feels like it did when I first got it: insane acceleration with unbelievable torque through the entire rev range. No service lights, either.

There’s nothing like the feeling of absolutely nailing a problem except the feeling of a fast car in its element.

Cali

December 4th, 2006 1 comment

“I hope the pacific is as blue as it has been in my dreams.”

That’s a line from The Shawshank Redemption, the second-best movie ever made. It was set in cold, rainy Maine. The best move ever made, Pulp Fiction, was set in warm, sunny Los Angeles.

I left cold, snowy Minnesota this morning, and now I’m in L.A. It was really difficult to sit on the beach just outside of Santa Monica this afternoon, and by “difficult” I mean “unbelievably easy.” The water was cold, but that didn’t matter, as the air was balmy. I relaxed and let the sun’s rays add color to my flesh and soul to my body.

Three weeks ago, I had never been to California. Since that time, I’ve been there twice; once to San Francisco and once to Los Angeles. From what I’ve seen of L.A., I much prefer the San Francisco Bay area.

San Francisco, the city itself, reminds me of Duluth, Minnesota: it’s hilly, it’s next to a huge body of very cold water, and it has a neat bridge. The landscape around the “Paris of the West” hints of my two favorite earthly locations: Minnesota’s North Shore and Switzerland’s Jungfrau region. They all boast big trees, frigid water, huge rocks, and rugged terrain.

In contrast, L.A. has smog. I think there are hills around it, but I can’t really see them because of all the haze. The area around Malibu is pretty, but it just doesn’t move me like the aforementioned three places. The one redeeming characteristic that L.A. shares with those magical locales is the water.

Few things are as relaxing as staring out over a huge body of water, one so large that it is impossible to see land on the other side. Lake Superior is large enough. So is the Pacific. When I fix my gaze on the horizon, a horizon that seems impossibly distant, all of my problems seem insignificant. They fade from conscious thought, mothballed for later contemplation. It’s hypnotic in a way, conducive to meditation. The infinite horizon, the repetitive crashing of the waves, the elegance of the shore — I love it.

Now I understand why people write about these places. Now I understand why people wax eloquent about the Pacific. Now I can place the Pacific in my own dreams.

Blur

November 28th, 2006 Comments off

The past two months have been a blur. Trips to Las Vegas, Chicago, Terre Haute, Dallas, and San Francisco. Patent applications. Business ventures. The beginning of the new season for my ice hockey team. Thanksgiving. Lots and lots of writing (but why?)

The next few weeks will see me visiting Los Angeles, being an official at a FIRST Lego robot competition, and playing hockey several times.

I’m busy, and I’m happy about it.

Heat

November 26th, 2006 4 comments

Ever wonder why you should turn the lights off in winter? I mean, it’s cold outside, and light bulbs are warm, so why not use them to heat rooms of a house?

Normal incandescent light bulbs are not very efficient, so they serve as better heaters than light sources. In the winter, I pay for natural gas to heat my home. I wondered if I could justify leaving lights on (out of laziness) by saving money on my heating bill.

First, the assumptions:

  • The light bulb in my living room is 95% efficient at heating the space
  • My furnace is 90% efficient at heating my living room
  • Gas costs me $0.76 per therm
  • Electricity costs me $0.09 per kilowatt-hour

What’s the cost of one BTU of heat from my natural gas furnace?

( 1 BTU / 90% ) * ( 1 therm / 100 000 BTU ) * ( $0.76 / 1 therm ) = $0.0000084 ( $8.4 * 10^-6 )

What’s the cost of one BTU of heat from my light bulb?

( 1 BTU / 95% ) * ( 2.93 * 10^-4 kilowatt-hr / 1 BTU ) * ( $0.09 / kilowatt-hr) = $0.000028 ($2.8 * 10^-5)

Well, that’s not good. It looks like it would cost me over three times as much to heat my house using incandescent bulbs as it would to use my furnace. I guess I’ll be shutting those unneeded lights off!

Of course, I’m not really concerned about power consumption — my home computer is on 24/7, and it draws the same power as many light bulbs. Brings back memories of heating my dorm room using my computer in college…

NorCal

November 15th, 2006 1 comment

I’m near San Francisco at the moment, Stanford to be exact. All I can say is: “Wow.”

On a related note, Tyler has introduced me to a new comic strip: PhD. I think this strip captures the moment nicely.