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Ford Oxygen Sensor Questions

An oxygen sensor is a mechanical device that is used to measure the ratio of air and fuel in an internal combustion engine of a vehicle. It helps to figure out the amount of air and fuel present in an automotive engine. These sensors are faced with a variety of problems which generate a lot of questions. In such cases, contacting an Expert for help is normally the best plan of action.

Below are frequently asked questions relating to Ford oxygen sensor that have been answered by the Experts.

How do you verify if a Ford oxygen sensor is slow or faulty when the check engine light has not illuminated?

To check a faulty sensor, use a proper scan tool. Another option to check the sensor is by observing the wave patterns using an oscilloscope. However, if a person is not skilled enough at verifying the sensor on their own, an Expert’s insight would be recommended.

What could cause a car to fail to start up after a Ford oxygen sensor replacement?

In some cases, a broken PCV tube could likely cause the problem mentioned. These tubes tend to collapse causing vacuum leaks from oil seepage. In other situations, the problem may occur due to jammed IAC valve, faulty rubber elbows or bad rubber intake manifold gaskets. Therefore, the best course of action would be to have the faulty codes scanned to determine the exact cause of the problem.

What could be the problem if ann oxygen sensor displays a code that indicates ‘02 Sensor signal stuck lean’?

The problem could be a faulty downstream heated oxygen sensor. When this is the case, the best possible thing to do would be to verify the wire harnesses and electrical connectors for any damaged wires. Additionally, inspecting the exhaust system for any leaks would be a good idea. If all the above mentioned verification procedures turn out to be fine a replacement of the sensor would be the best possible mechanical recourse.

What could be the possible reason for a car to not power up even if the Ford oxygen sensor on it has been changed?

A problem like this might occur if the vehicle has a vacuum leak in it. In most cases, the leak could be caused either by a cracked manifold gasket or a leaky injector O ring. However, in some situations, a stuck open injector or a shorted out oxygen sensor wire harness may likely lead to causing this problem as well. Other times, a defective PCM or damaged software could also cause this trouble to occur.

Why would a car display an error code that indicates a faulty upstream heated Ford oxygen sensor?

A car would indicate an error code like this if there is an exhaust leakage near the oxygen sensor. Usually, air leaks can also be one of the other reasons for this problem to occur. Thus, in this kind of a scenario, what a person may be able to do is to perform an extensive testing to find out the true cause of the fault. Alternately, the person could also choose to seek an Expert help to fix the problem.

Consulting an Expert is very important if faced with any Ford oxygen sensor related problem. This is especially true when a person may not have the right knowledge on what a particular error code may indicate. In some cases, they may not be aware of the simple removal and installation procedure of the sensor. While in other situations, they may need information about the exact location of a sensor on a vehicle to gain access to it. If you need clarification about your specific situation with respect to issues related to an oxygen sensor, you may ask a Ford Mechanic Expert to evaluate your case details and provide a mechanical insight.
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