DIY     OBD-II Codes     Fix your Car     Repair Manuals     -Forum-

Advertisement  [ ? ]

Site Links


Posted on: Monday, March 30, 2009

Todays vehicles are being equipped more and more with turbochargers. To understand what they do, we'll explain how they work. A turbocharger is made up basically of 3 sections: a center body consisting of the shaft housing, an intake housing and an exhaust housing. The center housing is a shaft with the turbine fins attached on each side; the bearings and seals of the shaft are in the center housing.
Turbo Schematics
Now, how it works. The exhaust of the engine flows through the exhaust housing and turns the turbine on the exhaust side, which in turn turns the intake turbine that pressurizes the air going into the intake. There is a wastegate on the exhaust side that regulates how much of the exhaust pressure is applied to the turbo and how much bypasses it. Without the wastegate, the pressure could build to a point of destroying the engine. The wastegate is the turbocharger's "failsafe", for lack of a better term.

The air to the intake is usually cooled by an intercooler, which uses the engine cooling system to reduce the high temperature of the air before it goes into the intake system. The cooler the air into the cylinders, the denser the fuel/air mixture can be. So for optimum efficiency, the air going into the cylinders needs to be as cool as it can be.

A turbocharger is a positive feedback unit, in which as exhaust flow increases, the turbine of the turbocharger increases, which increases the pressure or boost supplied to the intake system. As engine rpms increase, turbo boost increases to a point where the wastegate regulates it.

Normally most problems occur with turbochargers when foreign debris gets into the turbine blades and binds the turbines or when the oil drain tube becomes clogged with hardened oil that has gone from the extreme heat of the turbo to the cooler oil drain tube. When the oil drain tube becomes clogged, the oil builds up in the center housing, having no place to go, it pushes out the shaft seals and often creates an extremely smoky engine.With regular oil changes and servicing, turbochargers can be pretty reliable.

>> All Articles

Post your Comment
  - no <, >, [ or ] tags will go through. URL will be converted to link

Total messages: 0