So I notice when I initially accelerate to 40mph, that my MPG is around 2-8MPG with maybe 1/8th throttle (this is most of my drive with stop and go traffic). Once I get up to 40mph, it goes to around 20-25MPG. Anyone else experiencing this?
My fuel economy has also been down since I put in the K&N, but this has corresponded with the coldest February here since 1875. I'm pretty confident this period has been the coldest 5 or 6 weeks I've lived through in 60+ years.
I keep a fuel log and last weekend I got around to loading the data into a spreadsheet which I use to track over the long haul and also calculate MPG to compare with what the car's computer estimates.
I found a couple interesting things.
First: This is the first vehicle I've owned where the on-board computer has reported worse MPG over a sustained period than the actual calculated value. Overall the calculated fuel economy was actually 2% better than the computer reported. This is a good thing. Previous Mopar vehicles I have owned tended to overstate their fuel economy.
Second: This has only been the case since the temperatures got cold. From June through September the on-board system reported 3% better than actual. From October through February it reported 6% worse.
So, not only is colder weather hurting fuel economy, which is a given, but it also appears that the algorithm used by the on-board computer makes it appear the fuel economy is worse than it actually is when the weather is cold.
The type of driving might also play a role, since I've driven very few highway miles during the fall and winter. So it could also be that the on-board computer overstates highway MPG and understates city MPG.
Whatever, as usual your mileage may vary.