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Peugeot Oxygen Sensor Troubleshooting

Do you need to decipher error codes being displayed regarding the oxygen sensor? Is the oxygen sensor the fault for the engine running rough? Replacing the sensor can be done by the owner. However, when repairs are beyond your knowledge consult with an Expert for additional assistance. Read below where Experts have answered many of these questions. 

What is a 'depollution system faulty' warning on a Peugeot 207?

This is a generic warning which could relate to a number of issues including faults in the ignition system the fuel injection system or emission system, to name a few. It could also indicate a faulty oxygen sensor. To try to replace parts on a trial and error basis will be futile and expensive. To eliminate guesswork a diagnostic scan to check for fault codes is the surest way to go.

After replacing a Peugeot 308 oxygen sensor why does the engine misfire and display codes P0300 and P0304?

These are misfire codes with no connection to the oxygen sensors. It could be that the spark plugs are past their useful life and due for replacement. An engine diagnosis with a scan tool would pinpoint the actual problem.

What could an advisory about a minor leak in the front exhaust of a Peugeot 206 mean?

Case details: The engine runs erratically.

There are several possibilities for an erratic engine. Check for small holes or splits in the air intake trunking which could cause air to be sucked in. An air leak here would result in wrong messages from the engine management sensors which would cause the engine to run erratically. The location of the hole, if there is one, is critical. If it is anywhere near the oxygen sensor it can upset the balance and result in an incorrect air/fuel mixture ratio. If the engine management light is on the problem merits a diagnostic scan which will indicate the implication of the hole and point out its location.

What can happen if the engine auto diagnostic light on a Peugeot is permanently on?

If the light is on it means that the engine management unit (ECU) has detected a fault. The fault relates to several elements including a defective oxygen sensor, catalytic converter or loose wiring. If the car continues to run with the light on, diminished engine performance can be expected in the best case or engine damage in the worst. It’s quite impossible to guess where the fault is and what its implications are unless the fault codes are retrieved by a scan tool.

Could an accident have caused fault codes P0171, P0704 and P0131 on a Peugeot 206 and what are they?

The fault codes are:

  • P0171 – Fuel Injection (Regulation of richness).
  • P0704 – Malfunction in the clutch switch input circuit.
  • P0131 – Upstream oxygen sensor, open circuit or short to earth.

It is possible for the car to run well even with these faults. But the catalytic converter and oxygen sensors both being very sensitive could have been damaged or affected in the accident. There are two oxygen sensors on the car on either side of the catalytic converter. They are there to control the converter and ensure that the emissions from it are good.

Why does an ‘anti-pollution fault’ message show up at random on a Peugeot?

Case details: The oxygen sensor downstream of the catalytic converter was replaced twice.

Since the warning comes on full time the vehicle needs to go through a diagnostic scan to check what fault codes are stored. The past history would suggest that the catalytic converter would need to be replaced.

Is it safe to drive a Peugeot 207 with a ‘depollution system faulty’ message?

A depollution fault could relate to many things – the catalytic converter, ignition system, fuel injection, faulty oxygen sensor, or even the quality of fuel. It’s quite impossible to say with any accuracy where the fault lies without a diagnostic scan. As long as the car is running normally without misfiring or loss of power it should be good to drive. However, it’s advisable to retrieve the stored codes through a diagnostic scan at the earliest.

Its very difficult to isolate an oxygen sensor fault because there are so many other elements which could give similar symptoms. In most cases, the only way to know for sure is through a diagnostic scan. However, Experts could be of help when Peugeot oxygen sensor problems are suspected. Verified Experts are readily available to answer all your questions. 

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