I have had this idea for a while of modifying a cruise control into a throttle lock. My best gas mileage comes not from holding a steady speed, but from holding a steady throttle. I use my ScanGauge to find my TPS (throttle position). If I want to got about 35, I hold it at about a TPS of 13. If I want to g0 40, then TPS is 14. 45-55 mph, I use a TPS is 15 or 16. I will try to just hold my pedal at that position, which is not easy. I love the ease of cruise control, but gas mileage can be better.
My idea is to modify a cruise control to hold the throttle at a fixed position, instead having it adjust the throttle to maintain speed. I think the cruise control receives pulses from the speed sensor, and it uses those to tell speed. If the frequency of the pulses increases, the speed has increased, so it lets out the throttle a bit. If the frequency drops, it increases the throttle. What if I made a small add on to send a fixed freqency to the cruise control. I could get the throttle adjusted to where I want it, say at a TPS of 15 by the ScanGauge. Then I would activate the cruise control. It would read the frequency from the speed sensor, which is now the output from my add-on device. It would read a certain frequency of pulses. Since the pulses would neither increase, or decrease, it would hold the throttle at that postion. It seems like it would work. I could also have a switch that would switch between the speed sensor input and the fixed frequency input. That way I could use it as either a cruise control or a throttle lock.
Another option is to buy a used cruise control, and gut the circuitry from it and make my own. I am guessing it is basically stepper motor of some sort. Of course, I haven’t done any electronics work like that for years, and it goes a bit beyond anything I ever did. I would still want to be able to hit the brakes, and have it release the cruise control. But I would no longer have it as a cruise control.
Too bad someone didn’t already make something like this.
According to my ScanGauge 2, I averaged 44.6 mpg on my drive to work today. I think this is the best I have ever done on the route. I did leave home a little late, so maybe traffic patterns were a little different than usual. I know there were a few places where I was able to drive a little slower, because I didn’t have someone riding my butt. I just took it very easy. I accelerated a little slower than usual, and coasted longer to stops. I think I also managed to catch a couple lights nicely so that I didn’t have to stop completely. Maybe the small aero modifications to the front of my car have helped a little too. The warmer temperatures have been helping my gas mileage. It was kind of discouraging over the winter to see my gas mileage fall from 40 mpg to about 32 mpg. 32 mpg is still great gas mileage for a 2000 Honda Civic. Way better than the EPA estimates. But 32mpg kind of sucks when you have gotten used to getting 40 mpg. But the 44.6 mpg this morning was great. I don’t expect to get that on the way home. I can be getting great mileage all the way home. But then the hill up to my house which has a 300 foot climb, usually causes my gas mileage to drop by 2 mpg or so.
Just got home from work. I was averaging 41 mpg when I got to the bottom of our hill. By the time I got into my garage, my gas mileage had dropped to 38.9 mpg. As I said, that 300 foot climb drops my gas mileage by about 2 mpg. It’s funny. The drive is 13.5 miles, and that .5 mile climb is killer!
In an effort to make my 2000 Honda Civic more aerodynamic, and improve my gas mileage, I have been playing with smoothing out the front.
I had seen references to the “World’s Fastest Civic” (http://www.turbomagazine.com/news/0801_turp_worlds_fastest_civic_bonneville/index.html). I liked the look of the front end. So I set about to mimic that on my Civic. I made covers for the fake vents, and made a partial grill block for the lower grill opening. I made them out of plexiglass, and spray painted them black. I attached them with doubleback tape. I drilled a couple holes in the grill block, and mounted the license plate. I have driven around with it a bit, and the engine stayed in normal temperature range. I will keep an eye on the temp. I don’t think it will be an issue. If it is, I can always remove the grill block.
We are doing a long drive today. It will be interesting to see what kind of mileage I get. The last time we did this trip, we got around 41mpg. But you have to take into consideration weather, traffic, fuel differences. But still.
This morning I stopped and got gas. I was going to get it at the wholesale club, but it was out of my way. So I stopped at the Mobil station. I pulled in, and grumbled when I saw the price was $2.45. Gas had been like 20-30 cent cheaper only a week ago. Well, my tank was pretty low. So I started pumping, and was watching the numbers changing. The pump was pumping kind of slower than they usually pump. And I was holding the trigger all the way in. I saw the number go over 10 gallons, and was kind of surprised. I thought I would have used slightly less than 10. But it was still going up. Geez, I guessed my gas mileage wasn’t as good as I though. I felt some hit the back of my leg (I was wearing shorts). I turned, and saw gas pouring out of the gas tube. I released the trigger. The pump never clicked off, when the tank was full. I normally fill it to the first click. But it never clicked. So there was a bunch of gas on the ground!
I went inside and told them that there pump never shut off when the tank was full. He said it was supposed to. And I said yeah, it was supposed to. So not only was I getting ripped on the price, a bunch of gas was wasted, just going on the ground. I was not happy.
And since I normally fill to the first click, this will throw off my gas mileage calculation for my next fillup.
I had heard that overfilling your tank can damage something. I think the evaporation canister or something like that. Hopefully nothing was damaged. Grumble!
I was looking around Target one day, and I noticed they had some Black & Decker 2 gallon compressors (BDCP200AV, same as BDCP200 but with a free auto vacuum) in their clearance area. They were marked @ $70, and there was a sign saying 30% off. I thought 30% off $70 was an unbelievable price. But I asked and found that the $70 price was already reduce by the 30%. I passed, but then a day later changed my mind, and decided to get it.
The compressor came with various adaptors, including a tire nozzle. But there was no gauge on that. So I went to Walmart, and bought a tire inflator tool that had a gauge.
This compressor is a great addition to my garage. With a 25 foot hose, it makes it easy to keep the tire pressure of my car at the proper levels. And by keeping my tires inflated, my gas mileage is improved.
The adaptor I got a Walmart is easy to use. It snaps on to the valve stem, and I just pull the trigger, and put in a burst of air. When I release the trigger, the gauge shows the actual pressure in the tire. If I go over where I wanted it to be, there is a button to release just a little air.