Davet18

The following is a do it yourself procedure for replacing the thermostat on a 09 Cayenne S. The change out is straight forward and took me around 4-5 hours. One word of advice, the thermostat housing does not have to be removed to remove the thermostat. I thought it did and wasted a bunch of time removing other components to remove the housing before I realized it wasn’t necessary. The thermostat is removed easily after the water pump is removed. The parts were purchased from Sunset Porsche who were fantastic in getting the parts to me overnight. As always thanks to Loren for his advice. Tools Pliers to remove hose clips Torx sizes T-30, T-40 Strap wrench for holding pulley when removing screws E-10 Torx socket Large adjustable wrench for serpentine belt tensioner Normal other tools, pliers, screw drivers, ratchet, extensions etc. 5 Gal Bucket Parts List 948-106-125-01 (1) Thermostat 948-106-533-00 (1) Seal for Water Pump 948-106-707-00 (2) O rings for Intake Transfer Pipe (Note, the O rings are shaped different than the original O rings. Originals were square with grooves and these are true round O rings. Torque Setting Water Pump to casing 7.5 ft-lbs Water Pump Pulley 17 ft-lb Intake Manifold and Side Covers- Cross-tighten all manifold bolts to 7.5 ft-lb; then final torque to 12 ft-lb. I could not find the 09 torque spec but found the 07 specs which were reasonable. Procedure 1) I always disconnect the battery before doing any major work and recommend it. 2) Drain Coolant System A. Allow engine to cool B. Remove Coolant Reservoir Cap C. Remove the front two splash pans under the engine and radiator D. From underside of vehicle disconnect the hose (Figure 1) and drain cooling system into a container (clean 5 gal bucket works) 3) Remove plastic around engine compartment (2 screws and 9 plastic snap screws) (Figure 2) 4) Remove intake manifold and piping A. Remove decorative 4.8 V8 cover by lifting off B. Remove intake piping by removing hose clamps and removing pins (Figure 3). The pins rotate about a quarter turn and pull upward and out. Be gentle they break easily!!!! 5) Remove Intake Manifold Side Covers (similar for both sides) A. Removing two T-30 Torx screws (Figure 4) B. Remove vacuum hose connective both side covers (Figure 4) C. Remove vacuum hose on right side breather (Figure 4) D. Lift the Manifold Side Covers from the center of the engine up and outward and they will lift off. Right side has a vacuum hose attached under the cover which needs to be detached. 6) Remove Intake Manifold A) Remove (5) T-30- or T-40 (forgot size)Torx Screws on each side of intake manifold (Figure 5) B. Move the Intake Manifold forward and remove vacuum line and electrical connection on the back of the intake manifold. The vacuum line and electrical connection wire are very short. I disconnected the vacuum line Tee shown in Figure 6 to make it easier to disconnect and reconnect the vacuum line. 7) Remove the serpentine belt A. Relieve tension on the serpentine belt by rotating the tensioner (Figure 7) B. Remove the serpentine belt from the water pump 8) Remove Water Pump A. Remove 3 Torx Screw on water pump pulley (Figure 8) using a strap wrench to hold the pulley from turning. B. Remove (5) M6 X 25 Bolts on Water Pump using and E-10 Torx socket (Note Reinstallation tightening sequence is clockwise starting with the top middle bolt. C. If the pump is stuck gently tap it with a plastic hammer or a block of wood and it should come off. 9) Remove Thermostat A. Locate the spring on the Thermostat and tie a wire around the spring. (Figure 9 &10) B. Using a screw driver or pry bar inserted in the wire loop as shown in Figure 10 and pry out the Thermostat and the Transfer Pipe. Figure 11 shows the Transfer Pipe (3) and Thermostat (4). 10) Installation is in the reverse order of the above with the following advice/precautions. A. When reinstalling the Thermostat make sure the new thermostat is all the way into the housing before inserting the Transfer Pipe. The Transfer Pipe has two seals that should be changed when reinserting the Transfer Pipe. Use a water soluble lubricant when inserting the seals. I tried pushing in the transfer pipe in by hand but it kept popping back out because of the new O rings. I used a flat pry bar to gently press the Transfer Pipe back in (Figure 12). The Transfer Pipe should be flush with the housing and should not stick out. B. Check all vacuum hoses for cracks. They get brittle over time and crack. When finished, I got a 5504 Fault Code using Durametric Software. I contacted Durametric because I could not find any information on that code. It turns out that the software is transposing the code so it should have been a 0455 code which is a vacuum leak. I found a vacuum hose cracked from moving it around to get the Intake Manifold off. C. The vacuum and electrical connection wire are very short on the back of the Intake Manifold. I disconnected the vacuum line Tee shown in Figure 6 to make it easier to disconnect and reconnect the vacuum line. Make sure they are firmly plugged in before setting the Intake Manifold in final position. D. Make sure the Intake Manifold is seated properly and no wires are under the back corner of the manifold preventing it from seating properly. E. Porsche recommends a vacuum fill of the cooling system. Since I didn’t have the equipment, I filled the cooling system through the Coolant Reservoir. I used the fluid I removed from the system so I knew how much needed to be put back in the system. I ran the vehicle for a little while, let it cool, and then continued to top off the system over the next few days. F. If you disconnected the Battery you will get a PSM fault which will go away after driving for a little while. The system has to recalibrate itself after Battery Removal. I hope this helps the helps. I wrote it about a week after I did the repair so I hope I haven't forgot anything.