Porsche Camshaft Defect Comes to Light

Drivers of some Porsche vehicles manufactured between 2010 and 2012 are experiencing a new defect that can cause engine failure and may result in injuries if a vehicle breaks down while traveling at higher speeds.  The problem lies in the aluminum camshaft adjuster bolts which have a tendency to sheer off, which prevent the camshafts from running. If this occurs in the camshaft that operates the vacuum pump, the power braking will also fail, which will result in an extremely dangerous situation especially if the driver does not have the strength to brake the car without the vacuum powdered brakes. The bolts themselves may also drop into the engine and cause the engine to fail.

This defect occurred in the 2012 Porsche Cayenne S driven by Matt Truscott, 17, as he was driving home through San Francisco on July 4^th, 2016. Matt noticed that the check engine light and the traction control light had come on, and both the engine and the power steering were losing power. “At the moment it broke, it started to make a strange noise, like there was no power,” Matt explained. “It was difficult to steer because the power steering turned off, and once I got to about 15 miles an hour, the car shut off so I had to wrestle the car to the side of the road.” Matt also noted that his brakes were much more difficult to press. “It felt like the pedal was basically going the entire way to the floor,” he recalled. Fortunately Matt was able to get off of the freeway and park the car safely on a side street.

Porsche Knows About the Defects

Since early 2015 there have been 6 official complaints to NHTSA regarding the quality of these bolts, and many unofficial confirmations of the issue on vehicle forums. This is an issue that Porsche has known about since at least 2013, as they have issued a voluntary workshop campaign (WC-22) for owners of the 2011 Cayenne S or Cayenne Turbo models. The text on that campaign informed owners that “due to a temporary screw connection assembly problem, existing threaded connections on the camshaft controller can become strained to such an extent that the function of the camshaft controller cannot be guaranteed over the service life of the vehicle.“ The full text of this bulletin can be found here: (Download WC-22). This workshop campaign however only applied to 3,509 vehicles in North America. Porsche also recalled 14,571 cars in China (2009-2011 Panamera and Cayenne Models) for the same issue. However, these campaigns did not cover all of the vehicles affected by the defect, a fact pointed out by Matt Truscott’s father, Alan Truscott. “[I had seen that] the cars had been recalled in China, just not in the U.S.” said Alan, “so clearly it is a known potentially dangerous and potentially expensive issue.”

Alan Truscott took it a step further to show us how Porsche knows about the defective bolts and is trying to quietly fix it. “I stopped in… to see how my mechanic was doing on replacing the camshaft,” said Alan, “he showed me the kit that… includes steel screws and new bracket ends for both sides… It is clear that Porsche has a kit to rebuild both sides of the camshaft with steel screws now.” Alan also claims that his mechanic attended Porsche training sessions during which the defective bolts were discussed by Porsche employees. We have attempted to reach out to Alan’s mechanic to get more information on what Porsche knows and what they have attempted to do about it, but have not received a response.

Reports from drivers of affected cars have varied on whether the manufacturer will reimburse for parts and service of said vehicles. It appears that most cars in which the camshaft has not stopped working have been serviced for free and had their bolts replaced, but some drivers whose engines have been destroyed by the defect have not had as much luck. Alan’s local Porsche dealership did not reimburse him for his camshaft and possible engine damage due to the car having 86,000 miles on it and being out of warranty, despite the car always having scheduled maintenance performed.

What Should Porsche Owners Do?

2011 Porsche Cayenne S

The vehicles affected are primarily 2011 Cayenne S models, but other Cayenne and Panamera models from 2010 to 2012 have been mentioned in forums from owners who also experienced their camshaft adjuster bolts shearing off. Our recommendation is that if you are an owner of any of these car models, take your car to a dealership and check if the bolts are experiencing any unusual wear. It may also be helpful to bring along a copy of the WC22 Workshop Campaign to show the dealership what issue you expect to be dealing with, as some owners have claimed that their local dealers did not know about WC22 or the camshaft issue in general. (Note: The forum has removed the post with Porsche owners’ comments about the dealership and no cached version is available.)

It would appear while this defect can have dangerous consequences, there have not been enough actual observed cases and complaints to NHTSA to launch an investigation into this issue that may lead to a mandated recall. A recall campaign for any manufacturer is costly – not only from service and replacement costs, but also in the damage that it can do to a brand. It is likely that Porsche would want keep all negative press to a minimum and therefore would want to deal with issue quietly – replacing the camshaft bolts in some cars that they know are affected, but not making a lot of effort to service every car that they’ve manufactured that may have defective bolts installed. However, if an injury or death were to occur due to a camshaft bolt failure, Porsche would absolutely be liable and could be determined to have been negligent in not escalating the issue to try to fix more of the affected vehicles. For now, Porsche drivers can only hope that the attention this issue is receiving will pressure Porsche to put their customers’ safety before their profit margins.