# 2012 versa check engine light



## nissankdb (Sep 17, 2020)

We have only been using this car for the last4 months and have spent several thousand dollars on repair shops. Looks like a nice car and only 54000 miles. So far no one has been able to get the check engine light to go off and stay off. The front exhaust sensor has been replaced 5 times and it keep blowing out which causes the light to come back on. Wiring was checked and found to be good. Now they want to replace the main computer$$$. Help please.


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## rogoman (Dec 16, 2004)

We need to know what the actual ECU fault code is that's turning on the check engine light. You can perform an ECU code readout with a portable scan tool to see what the fault codes are. The tool can be purchased at most auto parts stores or online at Amazon.com. Post the actual codes here on the forum so that we may be able to help you further. If there is one or more fault codes set, they can help point to the malfunction.

O2 sensor failures can be caused by various contaminants that enter the exhaust. These include silicates from internal engine coolant leaks (due to a leaky head gasket or a crack in a cylinder wall or combustion chamber) and phosphorus from excessive oil consumption (due to worn rings or valve guides).

It could also be a lean condition in your engine that's causing failure of the sensor. You could look at the old one next to a new one and notice if there are any indicators of melting or evidence of severe heat damage.


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## nissankdb (Sep 17, 2020)

rogoman said:


> We need to know what the actual ECU fault code is that's turning on the check engine light. You can perform an ECU code readout with a portable scan tool to see what the fault codes are. The tool can be purchased at most auto parts stores or online at Amazon.com. Post the actual codes here on the forum so that we may be able to help you further. If there is one or more fault codes set, they can help point to the malfunction.
> 
> O2 sensor failures can be caused by various contaminants that enter the exhaust. These include silicates from internal engine coolant leaks (due to a leaky head gasket or a crack in a cylinder wall or combustion chamber) and phosphorus from excessive oil consumption (due to worn rings or valve guides).
> 
> It could also be a lean condition in your engine that's causing failure of the sensor. You could look at the old one next to a new one and notice if there are any indicators of melting or evidence of severe heat damage.


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## nissankdb (Sep 17, 2020)

I used a obd2 reader to check the codes and the same and only code that shows for the last 4 months is: P2A00- o2 sensor circuit range/performance bank1 sensor1 ??


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## steveX (Dec 20, 2019)

In my experience, when an OBD-II equipped vehicle has stored a P2A00 code, it means that the powertrain control module (PCM) has detected a malfunction in the upstream (or pre catalytic converter) oxygen (O2) sensor or circuit.

It can also be a problem with the catalytic converter not transforming the emission gas to legal amount. You should take the vehicle to repair shop that does state automotive inspection and have the vehicle tail pipe gas tested to see if it pass EPA gas emissions requirement. Also the ECU driver(microprocessors) could be at fault.


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## rogoman (Dec 16, 2004)

nissankdb said:


> I used a obd2 reader to check the codes and the same and only code that shows for the last 4 months is: P2A00- o2 sensor circuit range/performance bank1 sensor1 ??


What the code basically shows is that there is either a constant lean or rich condition. An ongoing lean condition will eventually ruin the O2 sensor; this looks to be your problem. Here are possible causes:

- Possible bad downstream heated oxygen sensor 2.
- Fuel pressure incorrect. Tee-in a temporary fuel pressure gauge between the fuel feed hose and the fuel rail. The readings at idle should be 51psi.
- Possible bad fuel injector(s). Run some good injection cleaner, like BG products 44K, through the system; give the cleaner about a week or two to do it's job.
- Intake system vacuum leak. To check the intake system for a vacuum leak, attach a vacuum gauge to a full vacuum source. With the engine fully warmed up, the reading at idle should be 18 - 20 InHg. At 3,000 RPM, it should be 21 InHg. If readings are under 18 InHg, check the intake manifold nuts to make sure they are tight. The gasket may have failed; spray a water mist at the gasket to see if the gauge reading changes. Also check the intake plenum bellows at the throttle valve and at the MAF for cracks or loose clamps.
- Exhaust gas leaks. Check for a cracked exhaust manifold or there may be a leaking exhaust manifold gasket.


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## lucas602 (Nov 9, 2020)

Any results here? +1 on the cleaner. Did this sit before they sold it? Run the tankout. Fill it and add a cleaner. I like seafoam. Give it an Italian tune up. Go up a long grade and downshift and get the RPM's up. Stop going to the guy that keeps replacing the o2 sensor and not solving it. Find an old man that wear suspenders to look at it.


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## steveX (Dec 20, 2019)

What about the transmission o2 sensor. Also check the muffler bearing and get vaccine.


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## lucas602 (Nov 9, 2020)

well


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