[hackish]

I've always felt that pulse and glide was a bad idea. A few weeks ago I managed to borrow a 5 gas analyzer and tried to see if I could determine the difference in emissions comparing a few different methods of saving fuel.

Unfortunately I haven't had the time to properly compile the data but from what I've seen it appears that shutting the engine off on my 1993 honda civic VX and then restarting it after only a 20 second coast produced approx 4-6x the pollution as running it for the same 20 seconds. Also, accelerating back up to the 100kph cruise speed caused significantly more pollution. The car has a factory 3 way cat installed and is well maintained. Since I only had access to the analyzer for an afternoon there were a lot of tests I wanted to do but wasn't able to.

One thing I regret is that I wasn't able to accurately measure fuel flow. I wanted to borrow an accurate aircraft fuel flow meter but was not able to. I was hoping to see if I could determine how the scheme managed to save fuel.

I may get another chance to use the unit in November. I'd offer to meet up and test with any other hypermilers around Ottawa but you'd need to have a bung installed in the exhaust system after the cats. I'm also interested to compare the results in November as I suspect the restart pollution is being caused by the cat temps dropping.

-Michael