Can a smog test detect a Clogged EGR valve?
Smog Test is also a good way to detect clogged EGR Valve If the EGR valve clogs or is completely being blocked off, it can no longer re-burn harmful emissions inside of the combustion chamber. The NOx emissions will flow unregulated through the combustion chamber and out of the exhaust pipe.
Why does an EGR valve need to be cleaned?
With the help of an EGR valve, a portion of the exhaust gas is allowed to pass through the inlet manifold where it displaces a certain amount of oxygen from the air, thus keeping the engine cooler and more efficient. High temperature and the excess amount of oxygen are the main sources of NOx formation.
What is the error code for an EGR valve?
Error codes like P1406 and P1404[2] can be seen in cases where the valve is stuck in an open position. You would then have to remove the plug and fill the empty spaces with a carbon cleaner.
How does exhaust gas recirculation ( EGR ) valve work?
Exhaust Gas Recirculation (EGR) is one of the simplest techniques that can be easily applied in a way to suppress NOx formation. How does an EGR work? There is a lot of air around us which is picked up by the engine’s intake manifold. Air is made up of roughly 20% Oxygen and 80% Nitrogen.
When does the EGR system cause high NOx?
The EGR system’s job is to re-route a small amount of exhaust gas back into the intake manifold to help reduce combustion chamber temperatures. As mentioned above NOx is created when combustion chamber temperatures reach above 2500F.
Why was my NOx too high on the smog test?
The only emission that was above the limit during the smog test was NO, however both HC and CO measurements were about halfway between “average” and maximum. A 2nd website said, “High NOX emissions are almost always due to a defective EGR valve (or some component that controls the operation of the EGR valve).
What causes a high NOx reading on a gas analyzer?
As a result of late intake valve opening, the vacuum will be low, causing the MAP sensor to see a load adding more fuel, causing high CO. The gas analyzer will read high HC, high CO, low O2, low CO2, and high NOx.
What causes high NOx and high HC in an engine?
With excessive preignition, the early flame front comes in contact with the spark ignition flame front. This will result in high HC, low CO, high 02, low C02, and high NOx. The horsepower of the engine will suffer as well.