Hi, I have a 2012 honda accord 4-cyl engine, automatic transmission with 71K miles. For the 2-3 past months, I have noticed a vibration and low humming noise at around 1500-1600 RPM. It is present when maintaining this RPM and worse when under load. The vibration and noise go away when accelerating past this RPM and when I put my foot off the gas pedal. The issue is not present when going 1500 RPM in neutral and is not speed/gear dependent. Also, no check engine light is on.
I was told the engine mounts were worn and has 3 of them replaced but the problem is still there. The shop who did it noticed the same problem. But said since there is no code there is nothing they can do. It seems to get better if the car does not sit cold for long. Like running errands. But is most noticeable before going to work and after.
Not sure what the issue is, any ideas?