Rep Power: 0

Is this even possible? The first tank of gas after the head gasket job, and I got 38.3 MPG in half city - half hwy driving?!

Could that gasket have been reducing MPG in other ways, even before it started causing the coolant leak?

Wow. I had no idea this car was even capable of that!

 
Rep Power: 518

Hard to tell. If something was amiss causing it to run inefficiently and got corrected during the work, then sure, but the typical head gasket seep problem on this engine doesn't usually kill off gas mileage.

If the head had to be machined, that could have a little bit of an effect on how it runs.

Weather break, it has been a lot warmer than a couple months ago?
Maybe your driving habits changed a little?

My own car can give me anywhere from low 20s to over 50 MPG depending on how I drive and which tires/wheels I have bolted on.


Did a Honda dealership do the work?

 
Rep Power: 0

Yeah but it never got more than 35.5 MPG, since we got it in August 2015.

Nope. I'm fairly light footed anyway. Not a hypermiler or anything, by any means.

I've almost never gotten less than 28 with this one, and that was from idling for an hour or so, on a tankful, with my partner waiting in the car for me, in weather that was too hot or cold to wait in, with the engine off.


[/QUOTE]Did a Honda dealership do the work?[/QUOTE]

Nope. A highly rated local mechanic shop.