Chargepipe-Intercooler O-Ring Seal, Hotside (AJUSA) - E82 135i, E9X 335i, Z4 35i

This is a large o-ring that seals the hotside chargepipe from the turbo to the front mounted intercooler on N54/N55 E82 135i, E90/E92 335i, and E89 Z4 35i/35is. Without this seal, or if it's damaged, charged intake air coming from the turbo(s) will leak on the intercooler inlet and result in a boost loss and poor performance. The seal has a more defined shape and is designed to fit a certain way over the intercooler inlet, which is why BMW calls it a preformed seal.

This seal is made by AJUSA, an aftermarket supplier of European auto parts. It has a two year warranty.