A Guide to the 2019-2023 Chevrolet Blazer Engine Oil Pressure Switch
That dashboard oil light is alarming, but the fix might be simpler than you think.
- Never drive your Blazer if the oil pressure warning light is on; have it towed and diagnosed.
- A faulty sensor is a common cause for oil pressure warnings, but you must confirm it's not a real pressure problem.
- For best reliability, consider using a GM Genuine OEM part or a premium aftermarket brand like Standard Ignition or Walker Products.
- Replacement requires a special oil pressure switch socket and may involve working in a tight space on the engine.
Is Your Blazer's Oil Pressure Light On?
Seeing the red oil can light on your dashboard is a serious warning. It means either your engine has dangerously low oil pressure, or the sensor that reports the pressure has failed. While actual low oil pressure can destroy an engine, a faulty switch is a common and much less severe problem. This guide will help you understand the symptoms, choose the right replacement part, and know what to expect for costs.
Symptoms of a Failing Oil Pressure Switch
When the oil pressure switch in your 2019-2023 Blazer starts to fail, it can give several clear signs. The most common issue is a false warning, making you think there's a major engine problem when there isn't. Here’s what to look for:
- Oil Pressure Warning Light: The light on your dash may turn on, flicker, or stay on, even when the engine oil level is correct.
- Check Engine Light: A failing sensor can trigger the Check Engine Light. A code scan will often show codes like P0520, P0521, P0522, P0523, or P0524. 🎬 See how to fix a P0521 code with this install
- Incorrect Gauge Readings: If your Blazer has an oil pressure gauge, a bad sensor can cause it to read zero, max out, or jump around unpredictably.
- Visible Oil Leak: Sometimes, the switch itself can fail and leak oil. You might see oily residue on the sensor or drips under your vehicle.
Warning: Do Not Drive
If your oil pressure warning light is on, you should not drive the vehicle. It is impossible to know if you have a cheap sensor failure or a serious lack of oil pressure that could ruin your engine. Have the vehicle towed to a repair shop for diagnosis.
Choosing the Right Aftermarket Part
For the 2019-2023 Blazer, you have a choice between OEM (Original Equipment Manufacturer) parts from GM and aftermarket brands. While aftermarket parts are often cheaper, for critical electronic sensors on GM vehicles, the choice requires some thought.
Many professional mechanics and experienced owners report that some aftermarket sensors can be less reliable or fail sooner than the original part. For a critical component like this, spending a little more on a high-quality part can prevent future headaches.
- Premium Aftermarket (e.g., Standard Ignition, Walker Products): These brands are established names in the aftermarket. They engineer their parts to meet or exceed OE specifications and offer a good balance of quality and price. Standard Ignition, for example, notes that they use high-temperature diaphragms for durability. Walker Products emphasizes that their sensors provide OE-level fit and performance. However, some users have noted that even within a good brand, there can be different quality tiers; for Standard Motor Products, the non-"T" series parts are often considered higher quality.
- OEM (ACDelco / GM Genuine): This is the part your Blazer was built with. It guarantees perfect fit and function. Many owners prefer to stick with OEM for electronic sensors to ensure maximum reliability and avoid compatibility issues.
Pro Tip: Check the Connector
Before ordering, it's wise to visually inspect the existing sensor if possible. Different engine options (2.0L Turbo, 2.5L, 3.6L V6) may have slight variations. Matching the connector style ensures you get the right part the first time.
Cost to Replace the Engine Oil Pressure Switch
The total cost depends on whether you do the job yourself or have a professional mechanic do it. The part itself is affordable, but labor can add up if the sensor is in a hard-to-reach location.
| Part / Service | Estimated Cost |
|---|---|
| New Aftermarket Part | $46.16 - $62.03 |
| New OEM Part | $65 - $115 |
| Shop Labor | $95 - $140 |
| Total Professional Replacement | $180 - $224 |
Frequently Asked Questions
Can I replace the Blazer's oil pressure switch myself?
Yes, if you have moderate mechanical experience. The sensor is often in a tight space on the engine block, sometimes near the oil filter or behind the intake manifold, and requires a special deep socket designed for oil pressure switches. If you are not comfortable working in tight spaces, it may be best to leave this job to a professional.
🎬 Watch this walkthrough of a similar oil pressure switch replacementAre there any recalls for the oil pressure switch on the 2019-2023 Blazer?
No. As of early 2026, there are no specific recalls or technical service bulletins (TSBs) from GM or the NHTSA related to the engine oil pressure switch for the 2019-2023 Chevrolet Blazer. Searches found recalls for brake pressure sensors on other GM models, but not for this specific part and vehicle.
What is the difference between an oil pressure switch and a sensor?
The terms are often used interchangeably. A simple "switch" just turns a light on or off at a set pressure. A "sensor" or "sending unit" provides a variable reading that is shown on a gauge. Modern vehicles like the Blazer use a sensor that performs both functions.
What happens if I ignore a bad oil pressure switch?
If the switch is faulty and causing a constant false alarm, you might become used to ignoring the warning light. This is dangerous because you won't know if a real, catastrophic drop in oil pressure occurs. If the switch fails to report an actual low-pressure problem, severe engine damage can happen quickly.
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Technical Specifications
OEM Part Numbers: 12661808
Provides pressure readings to the ECU and dashboard gauge/light. Typically has a 3-pin electrical connector.
We Have This Part in Stock
The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
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