Here we have a 2016 Volkswagen Tiguan SEL in need of a new turbo assembly, which seems to be a common issue with these. The turbocharger is a system of two turbines connected by a shaft in the middle. Exhaust from the motor forces one of the two turbines to spin from the exhaust pressure which forces the other turbine to spin, pressurizing fresh air into the engine intake (cold side). This pressurized increase of air coming into the intake means the engine needs to burn more fuel to keep the air/fuel mixture just right. The results are an increase in engine power without having to change the displacement of the motor.
Unfortunately for us, New Jersey and most of the other states in the northeast have to deal with problematic rust on our vehicles. This can be challenging for technicians as bolts get seized or rot away and break sometimes. This Tiguan is a victim of what seems to be a common issue on these models, a failed turbocharger system. When a turbo goes bad, some of the symptoms can include loss of power, smoking from the exhaust, and noise. In addition, one of the studs that fastens the turbo to the motor also has a tendency to corrode and break during turbo removal. This one specific stud sits in the back of the engine by the firewall, and is the only stud that does not enter the head perpendicularly but on an angle. While attempting to remove the turbo, we ran into this problem, presenting a challenge.
After multiple failed attempts to remove the broken stud with no room to work with and only a mirror to see with, the customer agreed to remove the head of the engine in order to remove this broken fastener. Removing the head gives us more room and decreases the chance of causing further problems. With the head off, we could also see that the timing chains were worn with almost 100k miles on them. We let the owner know what we found, and they agreed to do the timing chains to avoid a bigger job down the road. Removing the head allowed us to finish the job with no further issues and now this Tiguan is back on the road and ready to go!