What is the P0151 Code on Chevy Silverado and How to Troubleshoot it?

Problems with the Oxygen sensor is just one of those petty problems with the Chevy Silverado. It takes some time in the Silverado to run through all of the self-checks for adherence to pollution regulations after any codes have been cleared. Particularly the O2 sensors, can take a while.

Wondering why I’m raving about the O2 sensors? Because the P0151 code on a Chevy Silverado is the code that indicates Circuit Low Voltage of the O2 sensor. Particularly with the Sensor 1 of Bank 2.

I’ll go over all the simple, affordable, and useful fixes for the error P0151 in this article. So pay attention and read until the end!

What Does P0151 Code Mean On Chevy Silverado?

The OBD-II generic code P0151 indicates that the voltage to the Bank 2 sensor (upstream oxygen sensor) is much lower than the Bank 1 sensor. The bank 2 sensor 1 O2 sensor is unable to raise the voltage output above. 21 volts.

The P0151 denotes a longer-than-2-minute period of low voltage for the O2 oxygen sensor. The ECM interprets this as a low voltage problem and sets the MIL (Malfunction Indicator Lamp) as a result. This could also be a sign that the exhaust has too much oxygen.

The P0151 O2 code indicates that your engine is either in extremely lean condition or that your oxygen sensors are malfunctioning (less likely).

Let’s look at what the different parts of the code P0151 signify:

• P- Powertrain, the assembly of parts that move your car forward.
• 0- Standardized Code (ISO/SAE).
• 1- Secondary Air Injection System.
• 51- Specific code. In this case the Internal PROM malfunction or wrong MEM-CAI.

What Happens When the Code P0151 On Chevy Silverado Appears?

Here are some symptoms of the P0151 code on a Chevy Silverado (as well as similar GM trucks) :

• You will get frequent check engine lights driving 40 to 50 miles an hour.
• You will lose voltage at high RPMs.
• You may get erratic/inconsistent codes of P0151. A generic scanner will reveal the code. (wanna know how to scan with a scanner and analyze data? Check here!)
• Up until you give the vehicle full throttle on a gentle grade, the truck operates well. It lacks power at higher RPMs (5000).
• Although it doesn’t affect the truck’s performance, it may cause the truck to run like crap.
• You will be running lean. It, however, may not smell that way, it rather might smell rich.
• The code P0151 will often accompany the code P0131. In that case, there may be some loss of power, misfire, or running rough. The misfire is usually identified by the dummy light blinking and finally going steady after driving.

What Causes Code P0151 On Chevy Silverado?

Chevy Silverado does present some issues that can cause the P0151 code to appear. Identifying its causes will be a step forward toward a Chevy Silverado with no code.

Here the possible reasons for the P0151 code are given below:

• A damaged O2 sensor is the most prominent cause.
• Engine running lean.
• Shorted Wire causing O2 sensors low voltage.
• Possible alternator with brushes not getting contact at high RPM.
• Marginal battery.
• Belt tensioner/belt issue.

Other Symptoms Of Getting P0151 Code On Chevy Silverado

Some other symptoms of the P0151 code are:

• Poor MPG.
• Rough idle.
• Failed emissions.
• High fuel consumption.

How To Fix The P0151 Code On The Chevy Silverado?

Although most people go on without doing anything about this problem, the issue becomes serious when it starts affecting the performance of the Silverado. However, most times it doesn’t affect the performance.

Here’s what you should be doing about the P0151 code on your Chevy Silverado.

1. Replacing the Oxygen Sensor

Inspection of the Oxygen Sensor:

Each side of the car contains two sensors. On the driver’s side, above the catalytic converter, is the Bank 2. (Bank 1 ison the Driver side).

The passenger side contains bank 2. The sensor 1 is located before the catalytic converter, and Sensor 2 is located either within or after it.

Inspect the sensors carefully. Check voltage with a multimeter. They will most likely have no voltage.

Steps to replace the Oxygen Sensor:

Once you have located the Bank 2 sensor 1 and checked to find damage, replace it. Follow these steps to replace it:

• With a jack stand, secure your vehicle.
• Remove the plastic clip from on top of the sensor. Slide the oxygen sensor removal socket through the firewall all the way up to the socket.
• Unscrew the screws from the ratchet.
• Take off the pigtail sensor connection.
• Now following the reverse procedures install a new sensor.

Just watch this 2-minute video for a better understanding of replacing Bank 2 sensor 1. For a further detailed understanding, watch this video!

2. Troubleshoot Wiring

I’d suspect wiring if you continue to receive the same codes even after a PCM swap. Verify any ground wires in the vicinity of the MAF harness. The wiring for the under-hood illumination may have an additional ground wire spliced into the harness region.

Keep in mind the grounds that connect to the engine in the back. An additional braided strap runs from the same location on the firewall. It goes to the frame on the passenger side heads on older (TBI) engines.

Solution:

Install an insulated crimp in place of the MAF ground. Try replacing the MAF ground as well with a new one. Make sure there are no extra ground wires.

3. Troubleshoot Leaked Parts

Inspection of the Leaks:

Steel exhaust pipes are made of rolled material and have a welded seam. This frequently rots and leaks.

The exhaust system starts at the engine’s combustion chambers and travels along the car’s undercarriage before ending in a tailpipe. This tailpipe can be seen externally.

There may be leaks around this area.

Troubleshoot the Leaks:

Get a damp wipe and sandpaper to clean the leaky area before applying the sealant. Take the heat wrap out of the package and submerge it in water for 30 to 40 seconds. This will begin the activation process.

Then take it off and squeeze any extra water out. Wrap the sealant around the rotten leaks, overlapping it on each side by a few inches.

Squeeze it to make the resin seep through the leaks. You may repeat this three or four times.

Other than a sealant, you may also apply an exhaust putty. Complete the initial cleaning steps as mentioned and apply the putty. Allow it to dry for 2-24 hours.

How Much Does It Cost To Fix The Chevy Silverado P0151 Code?

Service Charge:

If there is no problem with the actual catalytic converter, you can change the oxygen sensor by yourself. You will be saving a lot of bucks, around $80-340!

But a reasonable labor charge should be around $70-90 to change a bank 2 sensor 1. This includes the change of parts.

Oxygen Sensors:

The cheapest items are always the priciest. Having said that there is always a service station that will do the work for less money. But make sure the sensor is an OEM or Denso model.

An oxygen sensor replacement for a Chevrolet Silverado typically costs between $280 and 320. While parts are priced between $230 and 260, labor costs are predicted to be between $45 and 60.

A local independent shop will cost about $350 for parts plus a $50 diagnostic fee.

Others:

Usually, it has been reported that the Silverado dealership overcharges their customers. For a simple P0151 code, you may be charged around $300-430.

Whereas, a reasonable deal for parts exchange should be $150-200 for parts and $80-90 for labor. If you are troubleshooting leaks, the cost will be much less!

However, if you take the car to a third-party dealership (such as Toyota), you may get a reasonable deal!

Overall, the cost to troubleshoot the P0151 will be $400-500.

Can You Drive Your Chevy Silverado With Code P0151?

Yes, you can definitely drive the Chevy Silverado. GMC cars rarely display any issues in performance with the P0151 codes. However, they might run rough at idle.

You may also notice more consumption of fuel. There may also be a poor exhaust emission situation with the Silverado.

Frequently Asked Questions (FAQs)

Conclusion

The post-catalytic converter sensors just keep track of the catalytic converter’s operation. But the pre-catalytic converter sensors gauge the amount of oxygen in the exhaust and affect how much fuel is injected. The PCM will set a code for the post-cat sensors if you turn off the converters.

It might be time for a replacement if the sensor is outdated or the original. However, I would first inspect the wire plug-in, wire ends, and wires in general.

So if you get the P0151 code, which signifies the low voltage in 02 sensor (Bank 2 Sensor 1), you will now know what it means and how to fix it.