30MPG. WTH!!!!

Have to agree with you, driving habits will cause this, some maintenance would not hurt tho, try cleaning your egr valve and pipe too.

 

200k miles and check all your six points too and my wife is doing 38-40 MPG (5.8-6 l/100km).
But my usual 20 miles trip out of the city to my brother in law is around 52 MPG.

 

Welcome, Nick. Is this your first winter with the 2010?

You've already done a good job of listing the reasons for your low fuel economy.

1) All cars get lousy mileage in the winter and get lousy mileage before they're warmed up. Combine those and you get super bad mileage. Just about the time your car is ready to give you those phenomenal mpg figures it's famous for, you shut it off.
2) The Prius normally gets better mileage on city streets than on highways, but a steady 40 or so mph is just about perfect.
3) This can be helpful if done properly. If done the way most people drive (jack rabbit starts and last second braking), it's really bad.
4) See #3.
5) So for 5-10 minutes you get 0 mpg and you're only driving 5-10 miles a day? I'd think that 30 mpg is remarkable. Most any other car would be getting you about 10 mpg.

Doing the regular maintenance that's been recommended will extend your car's life and might get you another 1-2 mpg. Also (very important) make sure your tires are properly inflated. Most Prius owners run them higher than the pressures listed on the doorpost. I keep mine at 42/40 and get very even tire wear.

 

This:

Plus this:

Plus this:

Equals 30 mpg. BTDT

Easiest way to beat this is with a plug-in vehicle.

 

dump it now, while you still can

 

And pay $5,000 over msrp for new or pay new car price for used? If the battery checks out, keep it (if he can do preventative maintenance himself).

Nick 2010, how many miles do you put on per year? How long do you hope to keep it. How long have you had it. Is the hybrid battery original?

 

but you get it on the sale end, it's a wash

 

true for a relatively new trade in but on a 12 Y.O. vehicle with a quarter million miles, not so much.

 

It matters less (at least in my mind) what @Nick 2010 Prius current drive is like as compared to what the other 235k 253k miles and servicing were like and at what mileage the mpg started dropping and by how much it dropped when the dropping began.

 

Yup! That's gonna make a huge difference.