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Which of these items is least likely to cause an exhaust emissions test failure as a result?

Which of these items is least likely to cause an exhaust emissions test failure as a result?

Spark plug hot range is least likely to cause an exhaust emission test failure as a result of excessive NOx emissions. This answer has been confirmed as correct and helpful.

When to diagnose an emissions test failure?

However, armed with a test report indicating what gases are high can help you determine what systems may not be functional. If the vehicle has failed as a result of high CO and HC, the CO failure should be diagnosed first. If the “Service Engine Soon” or “Check Engine” light is on it should be diagnosed prior to any emissions diagnosis.

What causes a high HC reading on an emissions 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.

Can a Honda Civic fail an emissions test?

[…] site that specializes in explaining the way a car runs created the article “DIAGNOSE – EMISSIONS TEST FAILURE (Smog Check failure)” to help explain why a car can fail an emissions test and require emission […] Failed emissions 1994 Honda Civic SI -1.6 ltr. – HELP!!!!! – Honda-Tech says:

What happens if any of the emissions components fail?

If any of these emissions components fail, emissions can increase. Along with these systems, other components such as spark plugs, plug wires, and filters can also increase emissions if defective. Emissions or smog is a generic term used to describe certain harmful gases in the exhaust. Hydrocarbons (HC), Carbon Monoxide (CO)…

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.

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).

Why did my car fail the smog test?

The vehicle has approx. 200K miles. (the odometer is broken) It seems to start and run fine, but it failed to pass a California smog inspection.

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

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Ruth Doyle