Prior to the revised EPA MPG estimates (2008?) the conditions that the govment used to come up with those MPG numbers were about as good as using a Ouija board to guess what mileage you’d get. For inst
Well one thing you can do is do whatever to keep your engine revs as low as possible. In “polite driving” you can probably get by without ever having to go over 2500. If it is a manual, you can have pretty good control over this.
As far as driving, that’s the best I can come up with.
You can sometimes bump your tire pressure up about 2 lbs higher than the spec to gain a little bit of fuel economy.
You might consider a performance air filter like a K&N to maximize flow.
If you have a OBDII USB cable like I do, you can get a real-time engine load display and you can try it with various accessories turned on and off to see where your biggest draw comes from. On a small engine like that, you could see 15% or more load by having the A/C on.
Anything that is belt driven is stealing power from the engine, if certain parts are old and worn they could be pulling too much on the engine as well.
To be honest that may be what the fuel economy was all along as Johnzcarz said it may be just how it’s rated, also keep in mind when they came up with that rating I’m sure they did everything they could to stack the deck in their favor to get the best numbers possible. In addition as an engine gets some miles on it there will be some compression loss due to wear that will effect the engine output which in turn will aslo effect fuel economy.
You have an ordinary gasoline engine Honda. When it was new, you could easily the estimated mpg. If you maintain the engine and the compression is still high AND the valves are adjusted, you could probably still get 32 per out of it if you’re doing legal speed down the freeway and it’s warmed up. If you commute about 7 miles to work, you won’t get your best mpg even if that 7 miles is straight down the freeway.
The EPA estimates have been an excellent indicator of mpg for decades, but if there’s an exception to that rule, it would the Prius (and any hybrid). Your mpg in a hybrid will vary greatly depending the kind of driving you do.
I have heard of people installing vacuum gauges in there vehicles to monitor engine vacuum while driving, Also a wide band 02 sensor setup would be another option but that’s overkill on a daily driver in my op