2015 Nissan Rogue. 46,000 miles. When sitting at stop lights after about 30 seconds there is what I would call a shuddering sound along with a vibration that lasts about a second. It only occurs when the a/c is on. When it does it repeats about every 30 seconds almost on cue. So I’m assuming it has to do with the a/c. Help is appreciated. Thanks.
Is this the same problem you asked about in your June 2017 thread ?
It’s probably the AC compressor’s clutch turning the compressor on and off. Not unusual. The compressor imposes some drag on the engine, which is transmitted to the crankshaft via the belt. You may also feel this as a little blips while under way at constant speed. If the belt is a little loose you may feel more “whip” but overall there’s not much to do about it.
I guess it is. Forgot about that.
On my Corolla I feel something like that when the electric radiator cooling fan turns on. It turns on based on the coolant temperature, and sitting at a stop light causes the coolant temp to gradually increase. If that’s what it is on your car, it’s normal. YOu could verify by parking your car when you get home from work but leaving the engine on. Pop the hood and watch what happens when the radiator cooling fan turns on when the coolant temp increases to the “on” temperature. Be careful, it starts spinning rapidly, without any notice. The cooling fan is also often designed to turn on when the A/C compressor turns on, independent of coolant temperature.