Strange Noise

1995.5 xtra cab V6 M/T 4WD e-locker 245,xxx miles.I have owned it since 2010, 160,xxx miles. No CEL, uses no oil between changes (5K mile interval), no coolant loss. I have a strange noise that has occurred maybe a dozen times during my ownership. The noise is similar to the sound of my winch only about three times as fast, lasts about 1 1/2 seconds, and has an "ugha" at the end. This noise has previously only occurred while the engine is running & only when not moving and only once. Until last Sunday. In Crown King, AZ. Temp was 33 F about an inch of snow on the ground, no wind. Noise occurred twice within about a minute while the vehicle was moving. Then about 3 minutes later it occurred three times within about 2 minutes when the truck was stopped & the engine shut off. Any thoughts? Ideas? WAGs?

 

Was it like a weeeeeeeeeeee or a ghhrrereree or maybe a bam! Pew pew pew? Seriously man doing a diag on a random occurring noise over the internet with that kind of information is pretty much impossible. Customer states vehicle is making random noise ro’s can be a pain in the ass when you have the truck right in front of you.

 

Yeah I know. Like I said it sounds like my winch only faster. Then at the end it is kinda like it "bounces back. Definitely a mechanical/electrical noise. I can't think of anything that could make that sort of noise with the engine running, let alone when shut off. And of course being random???? Not really worried about it just thought somebody might have some thoughts. What else do I have to occupy my brain?

 

EVAP canister probably. Mine makes some noise but usually when it's not running and in warm weather, mostly after it's been driven. Not sure it's an issue. Mine has done it for the 50k miles I've had it.

 

That's a thought. Any way you know of the test/try to reproduce the sound?

 

Open the hood after driving it and stand over the EVAP canister. Mine is right behind the battery. Believe it's just equalizing pressure through those two round rubber turrets on top.

 

Here ya go:
https://www.tacomaworld.com/threads/odd-noise-after-turning-truck-off.625614/

 

I had my 98 for three years before I heard that noise.....
my charcoal cannister was equalizing....

It was super faint.....had to have complete silence....about 2 seconds long....


After reading up, some of these as they age or fail ....they can become noisy....