What Causes high NOx readings?
Advanced timing or a poorly functioning cooling system can push combustion temperature high enough to affect NOx levels. If your car is equipped with an EGR valve, it should be checked for proper operation and possible carbon-clogged passages.
How is NoX sensor reading correction in diesel engines?
In this paper, we investigate NOx sensor reading correction in diesel engine selective catalytic reduction (SCR) system applications. It is well known that the urea-based SCR system is promising to remove engine-out NOx emissions and achieve strict legislative emission regulations.
Why does my car have a high NOx reading?
High NOx Readings and Causes! We at Discount Converter sometimes get calls from customers who have been told they need a new converter because their vehicle has tested showing HIGH NOx readings. A catalytic converter WILL NOT by itself reduce HIGH NOx emissions.
Can a catalytic converter reduce high NOx readings?
In no way will a catalytic converter reduce excessively high NOx levels. If the EGR system were not functioning properly, as a result of a plugged or partially plugged passage, inoperative EGR valve, inoperative vacuum control system, or an electronic malfunction, the controlled exhaust flow would not occur.
What to do if your NOx reading is high?
This type of diagnosis may require a borescope to visually inspect pistons, cylinder bores or valves. To repair this, a chemical top end cleaner may help. If the vehicle is not running rich, the gas analyzer will read high HC, low CO, high O2, low CO2, and high NOx.
In this paper, we investigate NOx sensor reading correction in diesel engine selective catalytic reduction (SCR) system applications. It is well known that the urea-based SCR system is promising to remove engine-out NOx emissions and achieve strict legislative emission regulations.
What to do if your car fails the NOx test?
If you own a non-EGR equipped vehicle, and have failed the emissions test for high NOx, pay close attention to the Catalytic Converter. Read about Catalytic Converter
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 does a lean fuel mixture cause high NOx?
A lean fuel mixture exists when less fuel then required is delivered to the combustion chambers or when more air then necessary is added to the fuel. In either case the lack of gasoline needed to cool the combustion chambers down is not present. Combustion temperatures increase causing high nitric oxide emissions.