A Guide to the Engine Camshaft Position Sensor for the 2005-2011 Cadillac STS
Understanding how to diagnose and replace a faulty camshaft position sensor to fix stalling and check engine light issues on your STS.
- Your 2005-2011 STS has two cam sensors if it's a V6, and four if it's a V8 Northstar.
- Common fault codes include P0340, P0341, P0345, and P0346, which often cause stalling and hard starts.
- For best reliability, choose an OEM (ACDelco) or OE-supplier (Delphi) brand to avoid repeat failures.
- Replacement is very easy for DIYers, requiring only basic tools and can be done in under 30 minutes.
Symptoms of a Failing Camshaft Position Sensor
A bad camshaft position sensor will almost always trigger the Check Engine Light. You may also notice one or more of the following symptoms:
- Engine Stalling: The engine may stall unexpectedly, sometimes while driving or when coming to a stop.
- Rough Idle: The engine may run unevenly or shake while idling.
- Difficulty Starting: The car might take longer than usual to start, or it may crank but not start at all.
- Reduced Engine Power: You may feel a significant loss of acceleration and overall power.
- Engine Misfires: The engine may make a sputtering or clattering sound. 🎬 Watch: See these common symptoms in action.
Choosing the Right Aftermarket Sensor for Your STS
When it comes to electronic sensors, not all aftermarket brands are created equal. For a sensitive part like the camshaft position sensor, choosing a quality brand can save you from future headaches. Using a low-quality part can lead to incorrect signals, causing the same symptoms to return or even creating new problems.
Brand Quality Tiers
Here’s a breakdown of the available brands to help you choose:
- Tier 1 - OEM & OE Supplier (Highest Trust): These brands are either the original part manufacturer for GM or are known to supply parts directly to automakers. They offer the highest reliability and are a direct replacement.
- ACDelco: This is GM's own parts brand and is the true Original Equipment part.
- Delphi: Originally a part of GM, Delphi is a major OE supplier and is trusted by many professionals as a top-quality alternative to the dealer part.
- Tier 2 - Reputable Aftermarket (Good Quality): These brands have a long history of producing reliable electronic components and are a solid choice if an OEM part isn't available.
- Bosch: A well-respected German manufacturer of a wide range of quality automotive parts.
- NGK (or NTK): While famous for spark plugs, their sensor division (NTK) is a highly regarded OE supplier for many car brands.
- Hitachi: An OE supplier for many Japanese automakers, known for excellent electronics.
- Standard Ignition (SMP): A long-standing aftermarket company that produces reliable sensors.
- Tier 3 - Value-Oriented (Use with Caution): These brands focus on affordability. While they may function correctly, some forum users have reported inconsistent quality or shorter lifespans with electronic sensors from these brands.
- Dorman: A very common aftermarket brand, but their electronic parts sometimes have mixed reviews for longevity.
- Walker Products, Spectra: Other common brands in the value price range.
Cost of Replacing the Camshaft Position Sensor
The cost can be broken down into the price of the part and the cost of labor if you have a shop do the work.
| Item | Estimated Cost |
|---|---|
| New Aftermarket Sensor (per sensor) | $23.10 - $66.95 |
| New OEM Sensor (ACDelco, per sensor) | $50 - $90 |
| Shop Labor | $75 - $150 |
| Total Professional Replacement (1 Sensor) | $100 - $240 |
Frequently Asked Questions (FAQ)
How many camshaft sensors does my Cadillac STS have?
It depends on your engine. The 3.6L V6 engine has two camshaft position sensors. The 4.6L Northstar V8 engine has four sensors, one for each of its four camshafts.
🎬 See this replacement walkthrough for the 4.6L V8 engine.My car has multiple sensors. Should I replace all of them at once?
While you only need to replace the specific sensor that has failed, the sensors were all installed at the same time. If one has failed due to age, the others may not be far behind. Since they are relatively inexpensive and easy to access, many owners choose to replace them all at once for peace of mind, especially on the V6 engine.
🎬 Watch: Step-by-step guide to replacing your camshaft sensor.What happens if I ignore a bad camshaft sensor?
Ignoring the problem can lead to more significant issues. Your car will continue to run poorly, get bad gas mileage, and may stall at dangerous times, such as in traffic. While it's unlikely to cause catastrophic engine damage directly, the poor running condition puts extra stress on other components like the catalytic converters.
Do I need to reset the computer after replacing the sensor?
After replacing the sensor, the check engine light should go off on its own after a few drive cycles. You can also clear the codes immediately using a basic OBD-II scanner or by disconnecting the battery for about 15 minutes. No special "relearn" procedure is typically required for this specific part.
Helpful Videos
Technical Specifications
OEM Part Numbers: 12588992 12577245 12593995
The sensors are located on the top of the engine, near the front of the valve covers. They are held in by a single 10mm bolt. The V6 engine uses two sensors, and the V8 engine uses four.
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.
- Cadillac STS: