What is a DISA valve BMW e46?
The DISA valve is located in the inlet plenum chamber and controls the variable length intake manifold giving better torque at low revs by closing, keeping the intake runner long. After higher engine speeds, it opens up and makes the intake runners shorter for more horsepower.
How do I know if my Disa valve is bad?
Symptoms of BMW DISA Valve Failure Poor fuel economy. Rattling noise coming from the engine. Loss of power at mid and high RPM’s. Lack of low-end torque. SES/CEL light and codes for running lean.
What happens when DISA valve fails?
The first things to usually that go bad on a DISA valve are the seals. As the flap closes, it relies on the seal to keep any excess air from moving through it. When this seal fails , you’ll get excess air in the engine, which ultimately results in poor fuel economy.
What is a DISA?
Defense Information Systems Agency ( DISA ) is a U.S combat support agency that connects the U.S military and government though IT and communications support. Originally known as the defense communications industry (DCA), the agency was created in 1960, partially in response to communication issues during WWII.