You have a chip monk, or an RB30 stashed somewhere under your bonnet....

Backspooling, Lovely terminology.

Its actually called Compressor surge. It can occur when the throttle plate is closed suddenly, or the turbo is compressing more air than the engine can use.
This usually only happens in high RPM and boost scenarios tho.

It actually spins the turbo back the other way.. you know... JOKING

expanding on what Paul said. when you back off the throttle body closes. and the air which is still getting pumped by the turbo has no where to go. being pressurize it normally squeezes out a blow off valve. But in my case i do not have one.

The charged air then tries to exit back where it came from (the turbocharger) but it simply hasn't got enough force to do anything except get chopped up by the blades which are spinning at a whopping 100,000+RPM. which results in a "flutter" noise you can here

Congrats on missing that bus.

And the light poles.

And oncoming traffic.

And the gutter.

And the parked cars.

evil_B4;146721 wrote:

Yeah, had a few close calls. Just got to watch out for grandma with her shopping trolley full of spam:lol:

I aint destroying this car. Mum's was enough

hey lance.

how did you crash your mums car if you dont mind me asking?

LE7SGO;146734 wrote:

hey lance.
how did you crash your mums car if you dont mind me asking?

So IS flutter actually bad for the turbo?
Not really a fan personally, but I guess it's impressively long? :Dntknw:

http://www.youtube.com/watch?v=jEUWEsqo … re=related


So not wanting to destroy a Car but running Turbo Without BOV :crazy:

Someone was asking about if it's bad?

http://en.wikipedia.org/wiki/Wastegate

Wastegate chatter myth

There is a common myth in the automotive world about so called "wastegate chatter" or "turbo flutter", a noise created on lifting off the throttle in a turbocharged car. The sound is commonly described as a chipmunk or a rattlesnake and is often stated incorrectly as being a result of the turbo's wastegate closing.
The noise is in fact the air compressed by the turbo passing back through the compressor wheel of the turbo after the airflow is abruptly halted by the throttle plate closing, called compressor surge. However, in some cases, i.e. where the throttle plate doesn't open fast enough or is set up to only react to high boost, some chatter will remain. Surge can occur on diesels when the turbo is attempting to pressurize the air at a higher pressure ratio than the compressor wheel can flow at a given speed. Diesels have no use for a Blow off Valve as they do not have a throttle plate.
The chatter noise is very noticeable on World Rally Cars, where anti-lag is used.
Bear in mind that a compressor stall like this causes huge amounts of wear on turbochargers and should be avoided in order to prevent damage to the wheel shaft and ball bearings, if the unit is equipped with them.

Gir;146775 wrote:

http://www.youtube.com/watch?v=jEUWEsqo … re=related

alexxx;146780 wrote:

wow, that would annoy the bejesus out of me driving it every day... cool a couple times but after that no way!

alexxx;146780 wrote:

wow, that would annoy the bejesus out of me driving it every day... cool a couple times but after that no way!