When the 996 series of the Porsche 911 was released in 1998, the world was already tremendously familiar with this two-door sports car, the Porsche flagship vehicle. Featuring a newly designed interior as well as a steeper windshield, the 996 was a top seller until Porsche replaced it with the next generation in 2004. One of the more serious issues affecting this model are failings of the Intermediate Shaft bearings.
The Intermediate Shaft (IMS) is the component in the Porsche that connects the crankshaft to the camshaft. As in many automotive components, there are many bearings that allow all the parts to move as they are supposed to, and these bearings are kept in a sort of boot that is filled with lubricant. Over time, this boot begins to harden, causing it to crack. These cracks in turn allow engine oil to begins drizzling into the bearing chamber, washing out the lubricant that is supposed to stay there, and causing an astounding amount of friction and heat to build up inside the boot.
As this process continues, the IMS begins to transmit its problems to the other systems (primarily the camshaft) in the vehicle, eventually causing metal parts to fragment and send hard debris into the engine itself. Unfortunately, there are very few outward manifestations of this problem as the car can continue running even if the bearings in the IMS have been compromised. You might be able to spot oil leaking somewhere between the transmission and the engine, but this might also be caused by a number of other less serious problems. At this point, you have lost not only your IMS but also the engine itself, and you are looking at a tremendously costly fix.
Seeing as how this problem was not tremendously uncommon in the 996 series, it might not be a bad idea to have your IMS system checked out by a local German auto maintenance garage. They can tell you whether or not you need to have the IMS replaced or repaired, and they can do it hopefully before any irreversible damage occurs.
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