Why is my O2 sensor still reading the same code?

If you have to drive 10 minutes before the Check Engine light comes on with the same code with the new O2 sensors, then the O2 sensor may be getting coated or contaminated where it can no longer read the oxygen content in the exhaust gasses and the voltage signal from the O2 sensor remains high.

When to reset the ECU after changing an O2 sensor?

Sometimes an O2 sensor fails, and you need to replace it. Once you’ve replaced your vehicle’s O2 sensor, you’ll need to reset the ECU so it can properly gather information from the new O2 sensor.

When did Bank 1 O2 sensor stop working?

I have a 2002 Chrysler T&C limited. In September 2012, squirrels chewed through the wiring to my bank 1 O2 sensor. After a quick and easy fix, there were no issues or codes. In February 2013, three error codes popped up (P0134, 0138, 0139), and the car was running sluggish and getting poor gas mileage.

When did I replace the O2 sensor in my van?

In February 2013, three error codes popped up (P0134, 0138, 0139), and the car was running sluggish and getting poor gas mileage. Three weeks ago, I took the van in to replace the O2 sensor. (I did not drive more than 40 miles since the codes came up).

Can you replace O2 sensor and still get check engine light on?

Replace O2 Sensor and still get Check Engine Light On. Replaced O2 Sensor and still get Check Engine Light On. 2 different shops did reads on my check engine light codes, I even paid $100 for one of them to do a full test of all sensors to identify which one was bad. Their diagnose was code P0141, oxygen sensor heater, o2 sensor had to be replaced.

What is the O2 sensor code on a Ford?

The Ford recall number is 08-S-05. Another thing I would like people to understand is the O2 sensor code does not mean it’s time to replace the sensor. It means that it’s time for some diagnosis and repair.

What are the symptoms of an O2 sensor failure?

(O2) Oxygen Sensor, Failure Symptoms: 1 Poor gas mileage. 2 Loss of power. 3 Black smoke from tailpipe. 4 Emissions test failure. 5 Rough idle. 6 Hesitation or stalling. 7 Check engine light comes on.

Do you need to replace your oxygen sensor?

Replacement of good oxygen sensors is one of the common mistakes that both seasoned auto repair mechanics and do it yourself driveway mechanics will make when tackling rich or lean diagnostic codes. I am not saying that these O2 sensor codes never require the replacement of the sensor itself.

When to replace O2 sensors?

Car manufacturers recommend replacing the O 2 sensor about every five years (one- and two-wire sensors) or 10 years (three- and four-wire sensors). However, silicon or carbon soot may cover an oxygen sensor due to a car repair or engine performance problems.

How often should O2 sensors be replaced?

Bosch recommends replacing unheated one- or two-wire O2 sensors on 1976 through early 1990s applications every 30,000 to 50,000 miles. Heated three and four-wire O2 sensors on mid-1980s through mid-1990s applications should be changed every 60,000 miles.

What is a bad O2 sensor?

Bad O2 sensors are one of those car problems that most drivers tend to postpone until more serious problems occur. These symptoms will rarely cause any immediate damage, but over time, if left unattended, they can cause damage to the engine and other systems mainly through improper air-fuel mixture.

Do I have to replace both O2 sensors?

Should I replace o2 sensors in pairs? It is best to replace your sensors in pairs. For example, if you replace the downstream left sensor, you should also replace the downstream right. However, on most vehicles produced since 1996, replacing one sensor (especially the front engine monitoring sensor) will cause the ECU to set a code for the other sensors.

What happens if you set code on downstream O2 sensor?

With this code set you will be running in open loop regardless of the reason the code is set. Constant open loop operation can’t be good for the cat. If this code only applies to the downstream O2 sensor then it will not affect the open/closed loop operation of the engine. The downstream O2 sensor controls the heat of the catalytic converter.

Is the O2 sensor on my Subaru not working?

OK, the heating circuit has failed on my downstream O2 sensor (CEL code P0141). As I understand it, this sensor does not affect fuel trim but only monitors exhaust. My Subaru still runs fine with a very slight decrease in MPG. Dealer wants over $300 to replace and says if the sensor is not replaced, damage will occur to catalytic converters.

What does O2 sensor 2 mean on a car?

Sensor 2” does not even describe what is wrong with the heater circuit. It simply says that there is a problem with the heater circuit; that’s all. It doesn’t say that there is a failure inside the O2 sensor. If this code is the only thing the dealer has, then, it’s a wild jump to the conclusion that the O2 sensor has failed.

Can a check engine light be an oxygen sensor?

It seems as though the check engine light and O2 Sensor codes have always gone hand in hand. I can’t even begin to tell you how many perfectly good sensors I’ve seen replaced for a rich/lean code, or as a cure to a service engine light that comes and goes. Fact is, when oxygen sensors were first being used, they did tend to fail.

What does it mean when your oxygen sensor says P0420?

Oxygen sensors are only a part of a greater system, meaning if the p0420 code (or p0141, or p0135) is thrown, that doesn’t necessarily indicate the oxygen sensors need replacement. Rather, there could be something else in that system does that’s causing the oxygen sensors to appear faulty.

Can a PCM replace an O2 sensor needlessly?

In my professional experience, the PCM is seldom the cause Nevertheless, they often get replaced needlessly But if the second shop arrives at the same diagnosis, it may be the exception to the rule. The O2 sensor produces it’s own voltage. The lower the voltage is the more oxygen there is in the exhaust gasses.

Fact is, when oxygen sensors were first being used, they did tend to fail. But manufacturers have been redesigning and tweaking these parts for over twenty years, and nowadays they are fairly bullet proof! Oxygen sensor codes no longer mean “replace the oxygen sensor”, and this mindset can be costly!

What happens if I Disconnect an O2 sensor?

If your “check engine” light comes on after you disconnect the O2 sensor, you will also fail emissions testing. You should only disconnect the O2 sensor in a vehicle you intend to use for racing or off-road use.

When to replace O2 sensor?

How often do you change O2 sensors?

Heated three and four-wire O2 sensors on mid-1980s through mid-1990s applications should be changed every 60,000 miles. And on 1996 and newer OBD II-equipped vehicles, the recommended replacement interval is 100,000 miles. A good oxygen sensor is essential for good fuel economy, emissions and performance.

What should I do if my oxygen sensor fails?

Always follow the instructions in your owner’s manual for Oxygen (O2) Sensor replacement. The Oxygen (O2) Sensor is a wear item and does fail over time. This will reduce the level of emissions your vehicle puts into the atmosphere. And, At the same time keep your engine running smoothly.

What happens when the O2 sensor is replaced?

It’s a common problem that when the code refers to the O2 sensor, then the shop simply replaces the sensor. But the problem in many cases is not the O2 sensor. And when the set of them are replaced for no reason, you end up with a car which now has non-OEM sensors, which aren’t as good of quality as what you had in the first place.

Are there any codes for an oxygen sensor?

There are a large number of codes relating to oxygen sensor faults. There are also a lot of faults that are often incorrectly thought to be caused by a bad oxygen sensor (also referred to as an O2 Sensor). The O2 codes relating to circuit faults can be tested fairly easily.

What’s the PCM code on an O2 sensor?

3 replacements of O2 sensor and still have P0134 code. Now told it is the PCM – Maintenance/Repairs – Car Talk Community 3 replacements of O2 sensor and still have P0134 code. Now told it is the PCM

When is it time to replace your oxygen sensor?

Oxygen sensors eventually need to be replaced in all vehicles. If your vehicle’s O2 sensor is faulty, chances are there will be signs! Check this list to see if it’s time to replace YOUR vehicle’s oxygen sensors: Sudden decrease in fuel mileage.

Are there any problems with the Mercedes oxygen sensor?

As evident in the information above, the efficient working of the Mercedes Benz oxygen sensor is better for the engine. Mercedes oxygen sensor related problems can lead to decreased performance and snowball into bigger issues with the car.

What happens to an oxygen sensor over time?

The Oxygen (O2) Sensor is a wear item and does fail over time. This will reduce the level of emissions your vehicle puts into the atmosphere. And, At the same time keep your engine running smoothly. What happens to Oxygen (O2) Sensors is that they tend to become fouled with carbon and sooty deposits.

How often should an O2 sensor be replaced?

Model years from the mid-1990s to present day, replace O2 sensors every 100,000 miles Model years from the mid-1980s to mid-1990s with heated three- and four-wire sensors, replace O2 sensors every 60,000 to 70,000 miles

Can a bad O2 sensor cause a car to have problems?

An oxygen sensor does not have to fail completely to give you problems. On the contrary, even a failing O2 sensor (sometimes called a “lazy” O2 sensor) may cause your car to have a few issues.

Where is the O2 oxygen sensor in the engine?

Also, The (O2) Oxygen Sensor is not able to measure the air or the fuel entering the engine. Because, the (O2) Oxygen Sensor is located in the exhaust and that where it reads the actual oxygen content in the exhaust. Depending on the year; make and model of your vehicle you could have anywhere from one to four (O2) Oxygen Sensors.

Why is my O2 sensor still reading the same code?