Stock exhaust sounds like an open exhaust.

[A2andres]

17 SQ5 with 112,000

Recently had to replace passenger side cat and replaced it with an OEM style version from MagnaFlow.

It’s been installed for about a month with plenty of miles without issues.

Yesterday I noticed a distinct rattle sound coming from around the passenger side cat.

It got progressively worse/louder where now it sounds like my car is running a dump tube.

I popped the hood to check things out and the passenger side cat has a threaded bung that I can’t recall had a “plug” in it or not. If it did, it doesn’t anymore.

Either that or maybe the flex section between the cat and the downpipe is knackered.

323499
323500


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[sepheroth86]

Looks like your O2 sensor came out.

[A2andres]

Just an update to close the loop. The magnaflow cat has an extra 02 bung that isn’t used and instead comes with a bung plug that somehow worked its way loose. I’m assuming my installer just didn’t tighten the plug enough.

These bung plugs are surprisingly hard to source but luckily I had the old downstream 02 sensor that I replaced when I had the cat replaced and just threaded that in there while I wait for the proper bung plug to arrive.

There - you can all rest easy now.


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[ThoseRings]

Just an update to close the loop. The magnaflow cat has an extra 02 bung that isn’t used and instead comes with a bung plug that somehow worked its way loose. I’m assuming my installer just didn’t tighten the plug enough.

These bung plugs are surprisingly hard to source but luckily I had the old downstream 02 sensor that I replaced when I had the cat replaced and just threaded that in there while I wait for the proper bung plug to arrive.

There - you can all rest easy now.


Sent from my iPhone using Audizine Forum


Pst...this is the "S4" forum...just saying, you know, so you can rest easy and all.