I needed to get into Manhattan yesterday and I found myself short for time. While getting into my car I resigned myself to the fact that I was going to take a MPG hit because I was going to drive pre-Prius style. I drive into Manhattan 5 or 6 times month and 48/49 mpg (displayed) for the trip each way is a lock. 48ish is also typically per tank. Anyway, I had to push. Instead of chilling at the speed limit, doing P&G when doable, staying off the brakes as much as possible, keeping an eye on the HSI, etc.. I drove strictly for the quickest trip posssible. Displayed mpg was over 55. I did the return trip just as aggresively to see if it was a one-off and got 55 mpg also. The Bottom line is, I'm not driving like a preacher anymore.
Someone asked me this very question during a "ride along" a while back. They were surprised that when they were in a hurry they often got better mileage than when they were trying harder. There are, of course, multiple factors. One factor, however, might be at the root of the matter: brisk acceleration. People forget that the lowest power draw of a vehicle is when maintaining a steady rolling speed. A lot of people focus on the dead-stop acceleration and perform a slow and steady ramp up. But when you're in a hurry, you throw that out the window and get up to speed quickly. Once up to speed, you let off the pedal and coast at an acceptable speed, timing the stoplights and not using the brakes as much. In my opinion, this is as much a factor as anything else.
Automobile Magazine did a comparison years ago whether light or full throttle acceleration was better for fuel economy. Turns out, heavier throttle acceleration away from a stop did better. They surmised this was because the engine was allowed to breathe easier due to a more open throttle plate, reducing pumping losses. This would also explain why people driving in Power mode report better fuel economy as the throttle inputs are greater.
eco mode highway traffic was light, Manhattan traffic weekday late afternoon was typical, congested very little over 20mph lots of stop and go. I just did the exact same trip highway traffic light, Manhattan traffic light, eco mode - got 58mpg. I'm convinced the heavy acceleration is the reason. Its the most significant difference in the way I'm driving. cool aint it?
I wonder if this has anything to do with the fact that the trip indicater shows 100MPG when you are stopped in traffic. I too have noticed very high MPG in stop and go traffic similar to what you are seeing and have wondered if the trip indicator is really telling the truth.
Could the summer fuel be a culprit? higher temps? I know they switch to summer blend on March 30, but on some gas station it takes a few weeks before old gas is replaced by new. Speaking of driving aggressive acceleration following "stealth" driving and full regenerative recovery doesn't seem to hurt MPG that much.
It doesnt show 100mpg when stopped but it does at 1 or 2 mph. The 2nd trip I did on the evening of the 19th there was only 5 minutes of stop and go traffic the rest was wide open. The car was new last summer and fall so probably mpg was lower due to newness. I guess the warmer temps are helping but it was only mid 50s on both trips. It will warm up here fast now, still mid 50s now though. Yea summer blend, I hadnt thought of that, gotta help some too. Still seems the primary difference was driving style.
Today I decided to be quite a bit more aggressive. Net result is 56.2 MFD. Note I still employ many advanced techniques where it is appropriate and applicable, it's just that I maintain higher speeds so it brings me out of sweets spots more often. Passing other cars is still fun. I achieved one of my best round trips the other day of about 61.3 mpg per MFD. This is utilizing many advanced techniques as much as possible, including driving in the right lanes as slow as traffic will allow. I estimate my very best is around 63-64 mpg (MFD), but I never measured it by the trip meter. I would say my round trip average is closer to 57-58 by the MFD, so today's result was not bad at all, given my speeds.
