[nicklvsa]

Hey folks had a quick question regarding my 2023 Camaro ZL1 1LE. I recently started noticing a squeaking noise when manually downshifting my A10 ZLE from 7th to 6th. The noise isn’t persistent and only happens when I apply throttle in 7th, going away quickly or when I downshift out of 7th. I don’t believe this vehicle has AFM (which seems to be the source of this noise on the SS’s) but was wondering if it could be the NPP exhaust valves. Curious what everything thinks here though - thanks!

[nicklvsa]

I was able to track this down to being the exhaust valves opening when the car is warm. I can reproduce the noise by swapping in and out of the track exhaust mode in the vehicle settings. I'm guessing the valves are dirty / covered in soot. Probably going to have a dealer look at them at my upcoming appointment

[arpad_m]

These NPP valves need periodic lubrication. I use Drislide and it works like a treat, here is how you can apply it: https://static.nhtsa.gov/odi/tsbs/20...34535-9999.pdf

[Boost Creep]

Originally Posted by arpad_m

These NPP valves need periodic lubrication. I use Drislide and it works like a treat, here is how you can apply it: https://static.nhtsa.gov/odi/tsbs/20...34535-9999.pdf

Nice!
Thank you.