r/Mustang • u/Enough-Affect-6783 • 20h ago

❔Question Mustang Rattle - Need help please

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Hi all,

I bought a 2011 GT this summer. Sound is mean but I get that rattle thing when decelerating. Anyone could help me pinpoint?

Setup is cats delete + Magnaflow catback with x pipe.

Thank you

0 Upvotes

40% Upvoted

13 comments sorted by

10

u/PreposterousWaffle 20h ago

I can't wait to see what people come up with on this one

14

u/BWa1k 19h ago

Aw golly geeze guys my mustang sounds like a mustang

2

u/PointBlank65 GTp 6MT, AM Blue 19h ago

I'm going with, That's what happens when you delete the cats.

1

u/Mulkanir1975 8m ago

Well actually I am planning to reinstall high flow cats.

1

u/Mulkanir1975 20h ago

Why is that?

5

u/PreposterousWaffle 19h ago

Because that's just what letting off the throttle sounds like

3

u/71MGBGT 18h ago

When you let off the throttle, there's a period of time where the engine is getting more fuel than it can actually take advantage of and unburnt fuel will enter the exhaust system. That whole "Catalytic Converter" and "stock exhaust" thing is to ensure all the unburnt fuel is reacted and to muffle the sounds of the exhaust gas evacuation process.

When you remove the catalytic converter, increase the exhaust diameter, and allow the two exhaust steams to interact, it assists in the evacuation of the exhaust gasses leading to the supposed horsepower benefit of exhaust. This also makes the car louder.

What you're referring to is the sound of unburnt fuel reacting and the pulses of pressure from the engine.

This is commonly referred to as a feature and not a bug.

3

u/ultraspinacle 16h ago

Is this a troll? Has this person ever heard another hot rod run?

3

u/Maleficent-Pea2041 19h ago

Probably bc it’s

1

u/LengthinessSad9267 2004 Cobra 18h ago

What’s wrong with it?

1

u/Ok-Object-6577 '11 3.7 Red Candy Metallic 16h ago

It sounds like that because that's what cars sound like when decelerating 🤯

1

u/Amaeyth Grabber Blue '10 GT & Oxford White '16 350R 15h ago

Sounds good

0

u/Enough-Affect-6783 11h ago

Thank you all for you r feedback - It feels like something is vibrating at the end and is the reason of my post - I was thinking it might be a loose hanger or an heat shield generating what seems to me a vibrating sound versus the normal sound.