Dear Scotty, huge daily fan here, I hope you love your new place.
2016 Frontier, 70K miles
Runs excellent but I can feel the vibration in the cabin only at idle rpm, red light etc.
Cleaned air throttle, no codes, no obvious symptoms of bad motor mount either.
Any advice?
Vlad
unbalanced flywheel?
How can this be checked?
Do you feel the vibration only while the car is in gear or in neutral too?
less in neutral and only when below 700 rpm or so
Clean the MAF sensor and check the idle control valve.
cleaned MAF and throttle body, no change
Odds are that your engine/transmission mounts are bad. You said you check them. How did you check them?
Had someone rev the engine in gear while holding the breaks and observed any movements, also observe going from park to drive and reverse
if it runs fine with no codes then possibly it is an engine mount or trani mount.