Your small intestine does most of the digesting of the foods you eat. If you have a malabsorption syndrome, your small intestine cannot absorb nutrients from foods. Causes of malabsorption syndromes include. 1  Celiac disease. 2  Lactose intolerance.  Short bowel syndrome. This happens after surgery to remove half or more of the small intestine. You might need the surgery if you have a problem with the small intestine from a disease, injury, or birth defect.
The exhaust manifold obviously carries exhaust away from the engine compartment. When the manifold fails to completely perform that function, fumes can enter the coach. This was not detected however in my coach so that telltale signal was missing. The manifold if leaking can reportedly injure the engine. And exhaust gases are used by the turbo system. If that is not performed well, you will notice a loss of boost (power) and mpg. If left unattended (repaired) the leak can also leak hot gasses into equipment and areas where it does not belong.
When the throttle is closed, a vacuum forms in the manifold. This in combination with the pressurized air from the turbocharger moves the piston in the valve up, releasing the pressure into the inlet of the turbo (Recirc.) or the atmosphere (BOV). blowoff valve is connected by a vacuum hose to the intake manifold after the throttle plate. When the throttle is closed, the relative manifold pressure drops below atmospheric pressure and the resulting pressure differential operates the blowoff valve's piston.