Engine sounds like crickets at very specific RPM

2008 2TR-FE 5 speed.

Between 2500 and 3000 RPM at specific throttle positions my engine makes this squealing sound that I can only describe as sounding like crickets under the hood. It's very reproducible, I can make the sound anytime I want by getting the RPMs in that specific range and feathering the gas pedal until the sound appears. It's not super loud, I can't hear it over wind noise at high speeds and I can't hear it with the windows up. Most obvious in 3rd gear next to a traffic wall of some sort with the window down. It has done this since I bought the truck at 130k miles, 200k miles now. Doesn't seem to be detrimental, just curious.

Has anybody heard this sound?

 

Idler pulley?

 

Maybe needs a belt and like the guy above could be an idler or the tensioner. Its easy to check when the belt is off

 

It's not a pulley. It's gas pedal position dependent. It doesn't do it if I'm decelerating, only cruising or slightly accelerating.

 

Heat shield on the exhaust?

 

Have you already cleaned the throttle-body?

I would also pull the belt and spin both pulleys by hand.
If your truck has over 100K miles, good chance your pulley bearings are due for replacement.

 

Any update on this? My truck just started doing this

 

Are you sure it’s coming from the engine. Do the crickets go away when you depress the clutch?

 

The crickets are there when I am on the gas past 2k rpm, and then when I coast one gear it gets much quieter, and when I coast out of gear it’s gone completely, if I rev it in neutral, it rarely makes the cricket noise

 

is it too quiet to get a video of? Interested in the sound. I used to hear crickets but found out it went away when I pressed my clutch in. Turned out my clutch pivot fork needed greasing

 

I would send a sound clip, however, the sound has gone away, which happens to be a slight bit more concerning

 

Never mind, it’s back, but it doesn’t do it as loud or as often. I’ll get a clip later today and put on here.

 

Did the crickets go away in a winding down fashion when you pressed the clutch?

 

No sir, it would go away completely. It definitely sounds engine related rather than trans since its winding down with rpms as you let off the gas.

 

Idler pulley. I had this issue intermittently until the bearing started to fail fast and it sounded like my power steering pump was low on fluid.

 

That’s also something I’ve been hearing! Ever since that noise started the power steering seems louder

 

Yeah, I used an automotive stethoscope to figure out which bearing it was while the engine was running. It stumped me for a bit until I did that.

 

So did yours only audibly “chirp” when the car was under load?

 

It started as a very inconsistent and almost random occasional chirping at around 2850rpm and under load. It then progressed to occasional screeching, then to the groaning and whining that sounded like low power steering fluid.

 

I also tried taking a video of the noise, but the phone wouldn’t pick up the noise