I have a 05 S with 142,000 on it. Replaced the Harmonic Crankshaft Pulley 2 years ago @ 135,000 and now am finding the same symptom happening; going uphill in 6th gear on a highway, pressing the pedal down and feeling a "slipping" sensation till it picks up. Is it possible to get a failure so fast with an inferior part? I don't remember the brand of the replacement part.
Lastly, it's still the original clutch; could this be a sign of it being worn down perhaps?
Thanks in advance!!

 

Your discription sounds like a clutch slipping problem…

 

Pit it in 3rd and let the clutch up and see if it slips. Other then that not sure if you can mark the outer side and inner side of the pulley, start the car and stop it then see if the marks are still lined up.

 

Put it in sixth on the highway, floor it and see if your RPMs climb without the car accelerating right away. If that happens it's more than likely your clutch.

 

Harmonic Balancers are more for damping torsional vibrations in the crankshaft to reduce engine vibration and number five main bearing failure. Swapping for a lightweight balancer is sold as a hot rod thing but typically causes more damage than good.

OTOH, even though it might cause vibration and bearing failure, it won’t make a clutch slip. Clutches are like brake pads in that the more you use them, the more they wear. And like brake pads, sliding also causes wear on the iron contact surfaces such as brake disks and clutch pressure plate (and flywheel).

Good luck,
Peter

 

Exactly this, this is the most easy way to test this.

 

not trying to get a sale but I have a barely used damper I'm selling for cheap if you end up needing one