[2006greyGT]

Sitting at a light my car just starts rattling. I pull over into a parking lot and look as good as I can and don't see anything wrong. check the oil,it is fine.. look under the hood but the noise comes from under the car. I get back in and back on the street and get on it to check if it has any effect on the power.No effect.I get home jack the car up and can't find anything by inspecting it with a flashlight. My neighbor comes over and runs the car up and down RPMs and I am inches away from the noise and can't determine where it is coming from. So I get a 1/2 inch hose and use it as a makeshift stethoscope and to my surprise it is coming from the cat on the drivers side. I didn't do any work to the car and don't know how the converters work and what could have come loose and making the racket I am hearing.

HELP !!!!!

 

[her name is ponie]

maybe your cats are dead

 

[Grabber523]

could be ping on one of your cylinders on that bank too...I would pull it off and see if it makes noise if you shake it...

 

[06GTMustang89]

+1 if not the cat then you got a ping in your cylinder like grabber said take it back tot he stealership so you can get yoru warranty to work haha

 

[Grabber523]

No waranty with the KB...causes would be either you have an injector not popping off quite right, or your tune didn't load up just right...what's your A/F at idle? If you've been driving on the stock tune it will be REALLY rich, which will foul your cats.

 

[06GTMustang89]

didn't see the KB in his mod list my bad hahaha

 

[2006greyGT]

it has the tune KB sent with the supercharger... been running just fine for 5 months. It mostly rattles just above idle at 1000-1500 rpm...

What is " a ping in my cylinder?"

 

[2006greyGT]

Wouldn't I get some sort of code if it was a fireing or injector problem...

 

[Regency 2007]

usually guys still take their cars to get custom tuned by a good mustang tuner after and kinda of poweradder install

I gotta say...

A part inside the cat is loose
Engine ping
Clutch chatter

one of the 3

 

[2006greyGT]

I had the SC professionally installed, They dynoed it after and made few if any tweeks to the KB tune.. it makes the noise if I hold it between 1000 and 1500 RPMs and while driving it happens only while the engine drops RPMs while the clutch is depressed, like a red light or making a turn.
If it is a "ping" what is the solution for that?
I don't think its the clutch because it really sounds like it is coming from the left Cat

 

[Lariat Trucker]

There has been an issue with the 'bricks" coming lose in the factory "cats". I really don't see any connection to the KB and it is an emission issue. Be cool and the dealer may just fix it under the emissions warranty. The only issue I can see might be the flowmaster "catback" pipe. Find a Roush dealer, they are usually more liberal about mods if they aren't the direct cause.

 

[2006greyGT]

I am tryin to figure out how to Isolate it but my best action is to pull the converter and see what I see

 

[FireryDriver]

It might be cats but I'd suggest getting the car up on a lift/jack stands and take a look around at your screws and see if there's any evidence of screws rubbing up against any part on the car. I know when I installed my cats the car started making this vibrating noise and after taking a look around under my car I saw a screw rubbing around so I flipped the screw around and tightened it, voila problem solved