What is causing these codes? P0141, P0139, P0140, P2188

[nnrouty]

Hi,

I have just joined the forum this week as I have an engine warning light on and I'm struggling to find the cause.

My car is a 2009 golf 1.4 tsi

The codes I have are:

P0141 - o2 sensor heater circuit (Bank 1 Sensor 2)
P0139 - o2 sensor circuit slow response (Bank 1 Sensor 2)
P0140 - 02 sensor circuit no activity detected (Bank 1 Sensor 2)
P2188 - system too rich at idle bank 1

Things I have tried already:

Replaced post cat o2 sensor
Replaced fuse for o2 sensors.

What could be causing these fault codes?

Any suggestions would be much appreciated.

Nathan

[Sam]

Welcome to VWAF

Other than the light, are there any symptoms?

The codes point to the rear o2 sensor but if you've already changed it, cleared the codes and the issues/codes still remain, I'd start investigating the wiring.

[nnrouty]

Thanks for the reply.

No other symptoms.

[Keithuk]

Welcome to the forum.


VAG Error Code: 16525/000321
EOBD II Error Code: P0141

Fault Location:
Oxygen (Lambda) Sensor 2 (G130), Bank 1, Heating Circuit - Circuit Malfunction

Possible Cause:
Malfunction Indicator Lamp (MIL)(K83) active.
Possible higher than usual fuel consumption.

Fuse(s).
Wiring/Connector(s).
Oxygen (Lambda) Sensor 2 (G130) heating circuit.

Possible Solutions:
Check/Replace Fuse(s).
Check/Replace all faulty Wiring/Connector(s).
Read Measuring Value Blocks (MVB).
Check/Replace Oxygen (Lambda) Sensor 2 (G130), Bank 1 heating circuit.
Heater circuit internal resistance 792 - 4560 Ohms.

Tech Notes:
The code means that there is a problem with the heater element circuit of the heated oxygen sensor. The control module monitors how long it take the sensor to warm up and start sending an adequate signal. The code is triggered when the sensor is taking too long to warm up.
Water getting inside the heated oxygen sensor connector can caused the heated oxygen sensor fuse to blow. Before replacing the sensor, check for the condition of the heated oxygen sensor fuse and connector(s). If the sensor and connector are OK, replacing the Oxygen (Lambda) Sensor 2 (G130) usually takes care of the problem.

When is the code detected?:
Current amperage in the rear heated oxygen sensor heater circuit is out of the normal range.

Description:
Oxygen Sensors or Heated Oxygen Sensors need to reach a minimum operating temperature of 750 degrees F to produce an accurate voltage signal. The faster the heated oxygen sensor reaches that temperature the faster the sensor will start sending an accurate signal to the Engine Control Module (ECM).

In order to achieve the require temperature, a heater element is included inside the heated oxygen sensor. The Engine Control Module (ECM) controls the heated oxygen sensor heater element based on signals from the engine coolant temperature and engine load. The Engine Control Module (ECM) controls the heater element circuit by allowing current flow to ground.

The Engine Control Module (ECM) monitors the voltage signal received through the heater element circuit and determines the state of the circuit by comparing the voltage detected with the factory specifications.


VAG Error Code: 16523
EOBD II Error Code: P0139

Fault Location:
Oxygen (Lambda) Sensor 2 (G130), Bank 1 - Slow response

Possible Cause:
Malfunction Indicator Lamp (MIL)(K83) active.
High Fuel Consumption.
Excessive Smoke from Exhaust.
Heating inoperative.

Wiring/Connector(s).
Oxygen (Lambda) Sensor 2 (G130).

Possible Solutions:
Check/Replace all faulty Wiring/Connector(s).
Read Measuring Value Blocks (MVB).
Check/Replace Oxygen (Lambda) Sensor 2 (G130), Bank 1.
Follow up with Readiness Screen Testing.
EWMA filtered transient time at fuel cutoff > 1.2 Sec.
In voltage range of 201 - 401 mV.
Number of checks = 3.

Tech Notes:
Replacing the Rear Heated Oxygen Sensor Bank 1 usually takes care of the problem.

When is the code detected?:
The P0139 code is set when the Engine Control Module (ECM) detects that the rear O2 sensor takes more time to respond between rich and lean than the specified time.

Description:
The Oxygen (Lambda) Sensor 2 (G130), after three way catalyst (manifold), monitors the oxygen level in the exhaust gas on each bank. For optimum catalyst operation, the air fuel mixture (air-fuel ratio) must be maintained near the ideal stoichiometric ratio. The HO2S output voltage changes suddenly in the vicinity of the stoichiometric ratio. The Engine Control Module (ECM) adjusts the fuel injection time so that the air-fuel ratio is nearly stoichiometric. The HO2S generates a voltage between 0.1 and 0.9V in
response to oxygen in the exhaust gas. If the oxygen in the exhaust gas increases, the air-fuel ratio becomes Lean. The Engine Control Module (ECM) interprets Lean when the HO2S voltage is below 0.45V. If the oxygen in the exhaust gas decreases, the air-fuel ratio becomes Rich. The Engine Control Module (ECM) interprets Rich when the HO2S voltage is above 0.45V.


VAG Error Code: 16524/000320/4025
EOBD II Error Code: P0140

Fault Location:
Oxygen (Lambda) Sensor 2 (G130), Bank 1 - No Activity Detected

Possible Cause:
Malfunction Indicator Lamp (MIL)(K83) active.
High Fuel Consumption.
Excessive Smoke from Exhaust.

Wiring/Connector(s).
Oxygen (Lambda) Sensor 2 (G130).
Inappropriate fuel pressure.
Faulty fuel injectors.
Intake air
leaks may be faulty.
Exhaust gas leaks.

Possible Solutions:
Check/Replace all faulty Wiring/Connector(s).
Read Measuring Value Blocks (MVB).
Check/Replace Oxygen (Lambda) Sensor 2 (G130), Bank 1.
Follow up with Readiness Screen Testing.
Signal voltage 0.40 - 0.60 V for > 3 Sec.
Sensor voltage load pulse vs. no pulse = 2.80 V.
Internal resistance > 40 K Ohms.
Exhaust temperature > 600°C.

Tech Notes:
Replacing the Rear Heated Oxygen Sensor Bank 1 usually takes care of the problem.

When is the code detected?:
The P0140 code is set when the voltage signal sent from the sensor to the Engine Control Module (ECM) is constant.

Description:
The Oxygen (Lambda) Sensor 2 (G130), after three way catalyst (manifold), monitors the oxygen level in the exhaust gas on each bank. For optimum catalyst operation, the air fuel mixture (air-fuel ratio) must be maintained near the ideal stoichiometric ratio. The Oxygen (Lambda) Sensor 2 (G130) output voltage changes suddenly in the vicinity of the
stoichiometric ratio. The Engine Control Module (ECM) adjusts the fuel injection time so that the air-fuel ratio is nearly stoichiometric. The Oxygen (Lambda) Sensor 2 (G130) generates a voltage between 0.1 and 0.9V in response to oxygen in the exhaust gas. If the oxygen in the exhaust gas increases, the air-fuel ratio becomes Lean. The Engine Control Module (ECM) interprets Lean when the Oxygen (Lambda) Sensor 2 (G130) voltage is below 0.45V. If the oxygen in the exhaust gas decreases, the air-fuel ratio becomes Rich. The Engine Control Module (ECM) interprets Rich when the Oxygen (Lambda) Sensor 2 (G130) voltage is above 0.45V.


VAG Error Code: 008584
EOBD II Error Code: P2188

Fault Location:
Bank 1, System too Rich at Idle

Possible Cause:
Malfunction Indicator Lamp (MIL)(K83) active.

Fuel pressure.
Injectors.
Air intake restricted.


As taken from my new EOBD II Error Codes

[nnrouty]

Thanks for the information.

So it looks like a wiring problem? As it seems to feature in the cause list of all the codes.

[nnrouty]

This weekend I noticed a smell of fuel outside the car.

Could this be related?

[Sam]

It's running too rich as per your first post, that would cause a fuel smell.

Could you smell fuel before or after you'd used the car?

[nnrouty]

I had just started the car when I noticed the smell of fuel. But hadn't started driving

[nnrouty]

Just found a leak in one of the vacuum hoses coming from a solenoid valve on top of the intake manifold.

Could this be causing the problem?