2014 Honda CRV, 126000. Never had a code. At 100k, I personally changed the belt, spark plugs, and attempted the valve timing(needed a mechanic to finish valve job). Coincidentally after that, I noticed my 29ish MPG has currently turned into 22.5 MPG driving the same route and same style over the past year and a half. Car seems to run the same and never had any issues with it.
Any ideas what it could be? Could a $100 scan tool give me any useful data on what it might be or is my car just getting old?
All the best
Jeff from Vegas
Sounds like a job for Scotty’s fancy scan tool. (You could try a basic one but it may not give you enough real time data, especially if you are not getting a CEL.)
Maybe recheck the spark plugs. Be sure they are the correct ones, not loosened, and are not fouled.
Check that all the little air hoses are connected. Make sure one didn't pop off.
Unless the valves are far out of adjustment, that shouldn't affect mileage.
Mass Air Flow sensor should be checked and cleaned.
And if you are near an Autozone, ask if they do the free scans. Free is good!
https://www.youtube.com/watch?v=NWCKvU2FmDc
