Noisy rattly exhaust sound / vibration until..

[Newbie GT]

Air pump turns off after around a min or so...

Anyone experience this? Cold 1st start only.



Cheers

[Sh4wry]

You need to put more info into your posts.

So this is only on start up?
What exhaust are you running?
Etc.

As always the exhaust is louder at start up because it's revving about 1.5k before it warns up and goes down to 700 rpm
What happens if you hold the revs at 1.5-2k same sound or is it gone after it is initially warned up.

Maybe your air pump is fucked? I'm not sure.

[Newbie GT]

Thanks Craig will do

Its xforce TBE
When car starts for initial 1st time in morning the exhaust at rear makes a rattle sound until air pump goes off after that quiet as a mouse. I have even got under the car before air pump turns off and held tighly both mufflers etc and no movement at all.

Hope this helps..

[kiahatsiu]

Heat shield on the turbo?

[bosc0]

Vote for one of the heat shields under the engine bay being a little lose.

[Rome_BRZ]

If you start it in your garage it could be shelves of the garage door rattling

[Newbie GT]

Thanks guys will check turbo heat shield

No even outside Rome it still does it. Only until air pump turns off..

[Rome_BRZ]

Thanks guys will check turbo heat shield

No even outside Rome it still does it. Only until air pump turns off..

Remove your air pump

[bosc0]

If you start it in your garage it could be shelves of the garage door rattling

Ain't no garage door under housing commision flats.... boss.

[Newbie GT]

Vote for one of the heat shields under the engine bay being a little lose.

If that were the case it would be vibrating all the time .

[Sh4wry]

Metal expands and contracts. Would explain why it rattled cold and stops when warm.

[Boostaddict]

The air pump recirculates all the air in the heads for pollution blah blah blah. So there is a change of pressure in the exhaust when it shuts off an returns to normal. It could just be a harmonic / sound wave type situation that the mufflers don't like and it changes the tone and or vibrates them.

When i had my 08wrx with the rear muffler disconnected (fully sick lebo style mod) it would sound awesome with the air pump on in the morning ( nice and deep note ) and when it switched off it dropped like 10db at least in tone and volume.

Dunno

My unedumacatededed guess!!

[Newbie GT]

The air pump recirculates all the air in the heads for pollution blah blah blah. So there is a change of pressure in the exhaust when it shuts off an returns to normal. It could just be a harmonic / sound wave type situation that the mufflers don't like and it changes the tone and or vibrates them.

When i had my 08wrx with the rear muffler disconnected (fully sick lebo style mod) it would sound awesome with the air pump on in the morning ( nice and deep note ) and when it switched off it dropped like 10db at least in tone and volume.

Dunno

My unedumacatededed guess!!

Thanks mate sound like you are right and thanks for reply

[paggaz]

The air pump recirculates all the air in the heads for pollution blah blah blah. So there is a change of pressure in the exhaust when it shuts off an returns to normal. It could just be a harmonic / sound wave type situation that the mufflers don't like and it changes the tone and or vibrates them.

When i had my 08wrx with the rear muffler disconnected (fully sick lebo style mod) it would sound awesome with the air pump on in the morning ( nice and deep note ) and when it switched off it dropped like 10db at least in tone and volume.

Dunno

My unedumacatededed guess!!

I think you're on the ball there as well.
When I got my 100 cell stainless steel cat fitted, I noticed cold start ups with the air pump on sounds much louder, as well as "tinny", which is normal for stainless steel.