What causes high HC emissions, high CO emissions?
What causes high HC emissions? Excessive HC results from ignition misfire or misfire due to excessively lean or rich air/fuel mixtures. What causes high CO emissions?
What are the results of the HC and co test?
The test results are summarized below: Essentially, HC and CO are far too high while NO is fairly low. Also, CO2 is low, indicating lean conditions. What are some possible causes, and some ways to investigate them, that could cause the test results?
What causes high hydrocarbon ( HC ) in a fuel?
What Causes High Hydrocarbon (HC)? Below are common failures which are likely to produce high Hydrocarbon HC. Hydrocarbons are basically raw fuel, otherwise known as Gasoline. High Hydrocarbon (HC) emissions are almost always a sign of poor fuel ignition.
Why does my car have low HC and co readings?
The low HC and CO readings indicate that the converter is functioning. The root cause of the problem is an engine which is emitting excessively high NOx emissions. These high NOx emissions may reduce the durability and efficiency of the converter
What causes high HC and high co?
High carbon monoxide levels are caused by anything that can cause a rich conditon. Excessive fuel pressure at the injector(s) Leaking fuel injector(s) Faulty O2 sensor(s) Defective fuel pressure regulator.
What causes high CO emissions?
Automobile HC emissions can come from the exhaust, the crankcase ventilation system and from fuel system leaks. Excessive CO emissions are caused by a lack of air or too much fuel. NOx is caused when combustion temperatures climb too high under loads or when the engine us running too lean.
What would cause of high HC levels in an emission test?
Let’s start by understanding what things cause a high HC reading. A high HC reading means the test found high HC (hydrocarbons) in your emissions. In other words, too much gas is left in the exhaust after combustion. High HC can be caused by improper combustion , where:
What causes high hydrocarbon emissions?
But high HC emissions can also be caused by burned exhaust valves (check compression), lean misfire (check for vacuum leaks, low fuel pressure or dirty injectors), or rich fuel conditions (fuel saturated carburetor floats, excessive fuel pressure, leaky injectors or a dead O2 sensor ).