Mystery Sound - Coming from...Somewhere.

[Spilsy Avid PP Poster! Find all posts View Profile Close Spilsy]

Here's a question with suitably little information to go on - sorry...

I have a weird sound coming from...somewhere. It sounds like intermittent little bursts of air - I'm pretty sure thats not what it is though.
It only occurs when I have my foot on the throttle and the car is moving - i.e. the sound does not occur if I am stationary and doesnt occur if I am not accellerating.
I first thought it was a stone or 2 in the tyre, but that sound would continue even if I wasn't accellerating. I then thought Brake rub - also, would continue if I'm not accellerating.

I dont think I can get a recording of the sound as the wind noise would be too much to pick it up unfortunately.

Any guesses would be appreciated!

Cheers.

[JimmyC Advanced Member Find all posts View Profile Close JimmyC]

Induction leak possibly? When exactly does it occur? Is it on high engine load (accelerating hard) or at any time the accelerator is pressed? Any particular rev range? Does it sound like it is coming from the engine area?

[Spilsy Avid PP Poster! Find all posts View Profile Close Spilsy]

Induction leak possibly? When exactly does it occur? Is it on high engine load (accelerating hard) or at any time the accelerator is pressed? Any particular rev range?

Pretty much from idle up - but only when moving.

Does it sound like it is coming from the engine area?

It sounds like its coming from forward of the drivers seat, it can be heard when either front window is down.

[JimmyC Advanced Member Find all posts View Profile Close JimmyC]

Some sort of induction leak is the only thing I could think of that sounds like 'air escaping' off idle. Check all of your soft induction hoses for leaks.

[diesel69 Junior Member Find all posts View Profile Close diesel69]

I think JimmyC could be on the money...... haven't had it on the Prado, but in the office (Western Star prime mover) I have experienced similar to what you describe which ended up being the hose between the intercooler and turbo.

[Carni Lurker Find all posts View Profile Close Carni]

Yep, induction or boost leak. Should be coming on when the turbo is spooling. Any noises when you're rolling but foot off the throttle?

[Spilsy Avid PP Poster! Find all posts View Profile Close Spilsy]

Yep, induction or boost leak. Should be coming on when the turbo is spooling. Any noises when you're rolling but foot off the throttle?

Nope. Only when the foot is on the throttle. I cannot replicate the sound when the car is stationary. I had a look in and around and couldn't find anything that looked abnormal. I'm not a mechanic though.

[JimmyC Advanced Member Find all posts View Profile Close JimmyC]

If it is a soft intake hose leak it would most likely be a small split that opens up under boost pressure.
Unsure about revving on idle how boost pressure acts as even though your turbo is spooled making boost there will be little 'load' on the engine making it flow easier and not forcing as much air out the leak.
If you aren't experiencing a major loss in power I wouldn't lose too much sleep over it and you'll end up finding it eventually. If it's a major leak you'll feel it. Had a turbo hose come off once (forgot to tighten the hose clamp) and the car will refuse to accelerate at all due to lack of power.

[Carni Lurker Find all posts View Profile Close Carni]

Had a turbo hose come off once (forgot to tighten the hose clamp) and the car will refuse to accelerate at all due to lack of power.

Had the same thing happen to me. Worked late on my drift car and then when it came to go time, had no power and was sooting everywhere. Forgot to tighten a hose clamp on one of the silicone joiners on my intercooler. Fixed that pretty quickly haha.