The VANOS seals degrading is a slow process that you will not notice over time. The cause is the selection of a seal material that is not suitable for high heat, high pressure environment that the seals are subjected to. This causes the seal material to harden and become brittle. The only solution is an expensive VANOS replacement or a DIY VANOS seal replacement.
BTW, I believe that this is the same cause that is resulting in the torque converter lockup issues due to seal failures, which is unfortunately, not as subtle or easily addressed.
The VANOS seals degrading is a slow process that you will not notice over time. The cause is the selection of a seal material that is not suitable for high heat, high pressure environment that the seals are subjected to. This causes the seal material to harden and become brittle. The only solution is an expensive VANOS replacement or a DIY VANOS seal replacement.
BTW, I believe that this is the same cause that is resulting in the torque converter lockup issues due to seal failures, which is unfortunately, not as subtle or easily addressed.
- Tony S., Cupertion, CA, US