What does the OBD detect in the exhaust?

What does the OBD detect in the exhaust?

It’s actually a common misconception that the on-board diagnostic (OBD) system on your car detects gases, but it doesn’t. It detects malfunctions with emissions equipment (the catalytic converter, oxygen sensors, fuel tank purge valve, etc.).

Can a faulty oxygen sensor cause a smog failure?

Needless to say oxygen sensors require periodic replacement. Failure to do so will more then likely cause a smog check failure. 4 out of 10 high CO failed smog checks will be due to a defective, damaged or lazy oxygen sensor.

What should I do if my exhaust gas sensor is not working?

If the sensor is threaded, clean the thread in the exhaust pipe with a cleaning tap. 4. Apply copper grease on the sensor thread only. Although some sensors are pre-greased, extra grease will prevent thread galling and reduce friction which could lead to over torque (especially with stainless steel thread.)

Why is my smog check OBD 2 incomplete?

There are several reasons why the monitors may be incomplete. If your car has recently been repaired for a problem that set a DTC (check engine on) and the technician cleared the DTC, he also erased the monitors. Also, if battery has been disconnected, replaced or needed a jump-start, the monitors may be erased.

It’s actually a common misconception that the on-board diagnostic (OBD) system on your car detects gases, but it doesn’t. It detects malfunctions with emissions equipment (the catalytic converter, oxygen sensors, fuel tank purge valve, etc.).

Why do you need an OBD for a smog test?

OBD Smog Test and the Catalytic Converter. The OBD system pulls together data from a vehicles catalytic converter, misfiring cylinders, oxygen sensor, and coolants to make accurate measures of emissions. The catalytic converter is one of the most important components of emissions control. Because its main role is to clean exhaust gases.

What happens when your car is not ready for an OBD test?

The status of the emission systems may also be reset by disconnecting the battery. After being reset, the emission systems on your vehicle will have a “not ready” status.

What are test only SMOG stations ( O2 sensor )?

Ask-A-Tech! What are Test Only Smog Stations? The Oxygen Sensor, also known as the O2 Sensor is the component responsible for delivering exhaust information to a vehicle’s emissions computer. Most late model vehicles will be equipped with both a pre-CAT oxygen sensor and a post-CAT oxygen sensor.

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