Welcome. You can use fuelly to track PHEVs, although some argue it's misleading as you're only accounting for the fossil fuel side of things, and kind of ignoring the fact that you used some electric each time. Kinda like me telling people how much my house costs to heat in natural gas, but ignoring the fact I occasionally burn logs on my open fire during winter...
Welcome. I am sad to say that Fuelly is pretty useless at recording mpg from a PHEV.
I'm back here after a long absence, I was planning to record mpg for fuel monitoring on my Honda CRV, but you say it's useless? I was quite surprised by that.
A hybrid is okay but there is no way of recording the electrical consumption of a Plug-in Hybrid. If you do a thousand miles on electrical power and only use one gallon of gas it will return about 1000 mpg!
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2006 Honda Jazz 1.2i-DSi S Vivid Blue Pearl