Good afternoon.
My accord has the issue - vibration when the car is in D or S and the break pedal is depressed (for example on red light). Eventually I have found that the Rpm during the red light or just when the car is stoped and in D and break pedal is depressed the RPM goes down till 580-600 and that is the reason why the engine starts a bit vibrating. Normal rpm is 650-750. So accordingly when it comes down lower then 650 the engine starts vibrating. would like to admit couple circumstances:
when I turn the lights on ( during D or S with depressed break pedal ) the rpm from 580-600 goes up and normalizing 650-750 and there is zero vibration. Early I thought that because of heating when it is on there is no vibration but the fact is that the turned on heating is not a reason of rpm stabilization, the reason is that when the heating is on the fan is working periodically in the engine compartment and as soon as the fan is on the rpm is stable (650-750 mostly 720) but when it off the rpm comes down again till 580-600. Before I learned it I have changed: all 5 mounts (original),spark plugs (original) , cleaned throttle body and despite of all this I have this uncomfortable vibration on my back seat and a bit on steering wheel.
So now I clearly know that the source of vibration is low (not enough Rpm while the car is in D or S with depressed break pedal) would like also to note that in R in P in N the rpm is normal 650-750. I also have measured the volts; without lights and heating in N , P ,R IS 12.3v but in D and S is 11.9-12.150v with turning lights is 14.2 v in all cases (P R D S)
If someone faced with this problem and terminate it please give me the feedback