Some early Porsche 3.4 liter engine (996) made from 1998 to early 2001 has developed some engine problems.
One of the biggest problems are cracked cylinder heads. the head can crack from the bolted faced across to a core plug. This leads to oil forcing its way into the water jacket. So look out for signs of contamination in the coolant.
Cylinder liners can also crack due to cylinder block’s torsional rigidity by driving the engine to extremes. Nine out of ten, it”s one of the center cylinders-two or five-and its always the lower edge that fails. The 996 engines are quite different to those on earlier 911s with individual cylinder liners.
All 996 engines have an intermediate shaft that runs the length of the block and is chain driven from the crankshaft. This, in turn, drives the twin camshafts on each bank of cylinders. At the end of this is a sprocket which turns on a bearing. The sprocket is retained by a small stud that can break, causing the bearing to fail. At first, this manifest itself as a noisy rattle, with turns into a death rattle as the cam chains come off, leading to further internal damage.
…so, lets go back to basic. maintenance of your vehicle is the key here. We are not trying to scare you or saying this cars are junk, it is just another car with some common problems. at the end there is not a perfect car out there.
Here are some pictures of our last cracked cylinder head replacement for your better understanding.
