Whirring sound when I rev and drive my 2005 nissan frontier crew cab

What is this sound I here when I rev my RPMs? When I am parked and rev the engine I hear a high-pitched electric whirring sound emanating from the engine. I get the same results when I drive. The car has 80K miles.

Also, there is a strange “electrical” smell apparent after the engine heats up, which comes from neath the hood. Are these two issues related? If so, or not, what could all this mean?



Phoenix, AZ

The smell and sound are likely associated.

By ‘electrical’ do you mean like wire insulation burning?

The ‘whirring’ sound, does it sound like a pulley spinning loose or perhaps does it sound like a wayward spark snapping but extremely close together? Eh?

Disconnect the belt from the alternator pulley and with a bit of side pressure, turn the pulley by hand. Any grinding or scratchy noises?

Is there any other abnormalities in vehicle/engine operation during/before or after this noise/smell occurrence?

I have a 2006 Frontier. I had the same sound. The dealer checked it out and it was the timing chain tensioner. Apparently the teflon coating is wearing off and scoring the timing chain. I was still under warranty so they fixed it for free.
Good luck