Rough spot a 1450 rpm

[harborman]

Lately when cold the motor has a slight rough vibration at about 1400 rpm. Car in neutral or drive. When it warms this mostly clears up. Either below or above that rpm it is normal. I am still having a hard start when hot but will check the pressure regulators next. Car has 45k original miles now. This roughness seems to clear after it gets hot. Otherwise it runs like a raped ape!