The failure.

The failure.

"In this Special Series, I document the backstory, unboxing and driving impressions of the S65 OE+ Carbon Plenum and the bespoke painted carbon variant

In this entry, we experience failure.

The S65 threw codes after the temporary seal managed to last 2 years. I put a quick reel together as I take off the faulty carbon plenum. As I went on a drive with to the original unit, I was reminded how muted it was.
- Matt


By Summer' 23, I started to experience MAP sensor pressure issues with codes triggering upon full throttle redline shifts. The errors started happening more frequently, and at lower RPMs. 

It eventually got to a point the car stalled going up a hill - completely. The engine shut down. Mass Air Pressure (MAP) sensors rarely fail on these cars, codes are most often a sign of an air leak somewhere along the intake system. 

I inspected the air tract across the engine bay and rapidly found the culprit. 

The driver side seal of the plenum had failed. 


My OE+ S65 carbon plenum was a returned unit due to a slight carbon weave error and a failed seal. 

I repaired it with urethane and sent it.  I knew windshield urethane would eventually fail as the seal is usually 2 component, catalyzed adhesive for a lifetime, warrantied seal.  

My experience is is not a representation of the usual experience with this product. What can I say: I wanted the noise without the wait - this was covid.

The plenum was off in 5 minutes - along with the two back rubber couplers. 

The couplers were taken off. Do not leave on the plenum, you risk permanently deforming or even tearing them. You'll hate yourself. 

Inspecting the plenum, the failure was pretty self explanatory. This shouldn't be possible. 

The rubber couplers were greased, and put back on the ITBs.

And voila, the OEM plenum got buttoned up quick. The rough plastic and being worn down make the installation fast. I didn't have to care for scratches and whatnot.

Enjoy the watch.

I put together a fast paced reel to showcase the rapid troubleshooting and a drive to validate this issue got solved. 

Mission accomplished!


Up next: we revisit the OE+ carbon plenum with a twist. 

I team up with René to pay homage to the GTS, and create a new variant of the carbon plenum. 

OE+ just wasn't enough.  

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