Exhaust Valve Rattle + Stuck Closed (Melted Plug)

[B58_ hwAyaq]

During/after a recent track day, I noticed my exhaust has a bit of a rattle (similar to rattling that others have posted videos of). CG Precision DP + stock catback.

I also noticed that even in sport mode, my exhaust is quiet like normal mode. After some investigation, I found that my exhaust valve is stuck closed.

I believe the rattle is coming from the valve.

I checked the fuse - all good.

BUT

I looked under the car, and I believe the plug/harness for the exhaust valve flap has melted.

Any guidance on replacing this? Not sure if it’s a plug on both sides (didn’t trace it back yet) and I can just replace it. Also haven’t tried to disconnect it (waiting for exhaust to cool) as it may be melted together (hope not).

Check it out:

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[B58_ hwAyaq]

Assuming the actuator side is still good, I’m betting I’d have to replace the whole plug+cable.

Anyone have a part number and/or know how far this cable runs into the car?

 

[sup.dc2]

Its the connector thats bad not the whole harness. Those ends can be purchased separately and you can de-pin the connector. Assuming that it's actually the problem because it looks fine its that housing that looks melted it may still be making contact.

 

[B58_ hwAyaq]

Updates:

• The exhaust rattle was from the little spring that connects the actuator to the exhaust flap (see video)
• The cable protection is melted a bit, but the wires look good (per @sup.dc2)
• The plug is melted/fused to the actuator.
• The part that rotates on the actuator is melted to the point where the actuator cannot be easily removed (see video).
• The actuator is very notch when trying to manually rotate it (see video).

Solution:

• Fixed rattle by stretching spring and reinstalling.
• Manually opened flap and pulled exhaust flap fuse.

Good to go (but flap does not change) and now normal mode sounds better. The "back to OEM" solution would IMO require depinning the wires on the actuator, repinning a new plug, and replacing the actuator completely.

Apparently rattles are common on all valved exhausts. For any car that sees track days, I am now personally leaning towards disabling the exhaust valve flap (BMW even has OEM dummy plugs for this) or going valveless if installing an aftermarket exhaust.

 

[NitroYellowMKV]

My exhaust valve broke a couple weeks back as well. I installed a new catback, and after a few days the exhaust valve started opening in normal, being half closed in sport, full open in normal, full closed in sport, and would randomly change position while driving, I would unplug and replug in and it would fix it for a few days and then start freaking out again, I replaced the actuator 3 times already and seems to still have the same issue so I have fully removed the actuator and zip tied valve open, taking it in next week to see if its the connector or the full harness went bad, or if its something coding related that needs to be reset or adaptions reset. Exhaust valves while they are great and I love having the option to shut it up, have always been a pita between rattles, and issues like you had.

 

[Pennium]

I have a similar issue, in this case that small wire extender is a goner for me. Can you please help me with a part number?

 

[B58_ hwAyaq]

I have a similar issue, in this case that small wire extender is a goner for me. Can you please help me with a part number?

Maybe this will help. https://parts.lakelandtoyota.com/showAssembly.aspx?ukey_assembly=2288173

If you’re talking about the electrical wire, I have yet to find that part number.

 

[quikslipper]

Question on the CG dp, just confirming it doesn't throw a CEL?

 

[B58_ hwAyaq]

Question on the CG dp, just confirming it doesn't throw a CEL?

Despite what others claim in their short amount of driving, yes, it will eventually come on. https://www.supramkv.com/threads/will-the-cg-precision-ds-1-catted-downpipe-throw-a-cel.20278/

Had 8k miles on the downpipe when I flashed to stock and got the CEL. Not sure when it would have come on if I was stock tune the whole time, but reports of no CEL have been on cars with lower miles on the downpipe itself. Get the AA if you want a no CEL guarantee without a flash tune.

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