A Guide to the Engine Crankshaft Position Sensor for the 2003-2010 INFINITI M45
Keep your M45's V8 running smoothly by understanding the signs of a failing crankshaft position sensor and how to choose a reliable replacement.
- Sudden engine stalling is the most dangerous and common symptom of failure.
- Hitachi is the original equipment manufacturer (OEM); using this brand is highly recommended for reliability.
- A recall (NHTSA ID: 03V-455) was issued for early models; check with a dealer to see if your VIN is affected.
- The most common diagnostic code is P0335.
Understanding Crankshaft Sensor Failure in Your M45
The crankshaft position sensor in the 2003-2010 INFINITI M45 is a known failure point, often causing sudden and serious engine problems. A key reason for this is a historical manufacturing defect. In 2003, INFINITI issued a recall (NHTSA ID: 03V-455, Infiniti recall numbers R3021/R3022) for improper solder joints on the sensor's circuit board. This defect could cause the engine to stall without warning, hesitate, or fail to start. While this recall primarily covered early models, the sensors on later models can still fail from normal wear and tear due to high heat exposure at the bottom of the engine.
Recall Notice: NHTSA Campaign 03V-455
Early model year M45 vehicles were part of a recall for faulty crankshaft and camshaft position sensors. The issue stemmed from bad solder joints that could fail under heat, leading to engine stalling. Before purchasing a new part, it is wise to contact an INFINITI dealer with your Vehicle Identification Number (VIN) to see if your car was affected and if the recall work was ever performed.
Choosing the Right Aftermarket Sensor
When replacing a critical sensor like this, brand quality matters. For your INFINITI, not all aftermarket brands are created equal. Some owners report that using cheap, low-quality sensors can cause the same problems as the failed part, or even introduce new ones.
Brand Tiers for Your INFINITI M45
- Top Tier (OEM Equivalent): Hitachi is widely recognized as the Original Equipment Manufacturer (OEM) for Nissan and INFINITI. Choosing a Hitachi sensor is essentially like buying the genuine part from the dealer but often at a lower cost. This is the most recommended option for reliability and consistent performance. NGK/NTK is another high-quality brand known for making OEM sensors.
- Mid Tier (Reputable Aftermarket): Brands like Delphi, Beck Arnley, and Standard Ignition (SMP) are generally considered reliable. Beck Arnley often sources parts from the original manufacturers, so you might find a Hitachi sensor in their box. These brands offer a good balance of quality and price.
- Economy Tier: Brands like Walker Products and True Tech fall into the economy category. While they are the most affordable, they may not have the same durability or precise specifications as higher-tier options. For a sensor this critical to engine operation, opting for a higher-tier brand is strongly advised to avoid doing the job twice.
Crankshaft vs. Camshaft Sensors
Your M45's VK45DE engine has one crankshaft position sensor and two camshaft position sensors. They may look similar, but they are not interchangeable and have different functions and locations. The crankshaft sensor is located at the bottom of the engine where it meets the transmission, often on the passenger side. Be sure you are ordering the correct part to avoid installation headaches.
Estimated Replacement Costs
The cost can vary depending on the brand of the part and the labor rates in your area. Many owners choose to replace this part themselves to save on labor costs.
| Item | Estimated Cost |
|---|---|
| New Aftermarket Part | $28.80 - $74.74 |
| Shop Labor | $100 - $180 |
| Total Estimated Cost (Aftermarket Part + Labor) | $128.80 - $254.74 |
Frequently Asked Questions
What is the most common symptom of a bad crankshaft sensor on an M45?
The most reported symptom is the engine suddenly stalling while driving, especially when coming to a stop or when the engine is warm. This may be followed by difficulty restarting the engine or a complete no-start condition.
🎬 Learn more about common symptoms of a failing crankshaft sensor.Will a bad crankshaft sensor always trigger a Check Engine Light?
Not always, at least not immediately. The engine may stall or run poorly before a code is stored. When the light does come on, the most common trouble code associated with this failure is P0335 (Crankshaft Position Sensor 'A' Circuit Malfunction).
Can I replace the M45 crankshaft sensor myself?
Yes, this is a job many DIY-ers can handle. It involves raising the front of the vehicle, removing a plastic undertray, and accessing the sensor on the lower part of the engine near the transmission bellhousing. It is held in by a single bolt and has an electrical connector. The main difficulty is the tight access.
🎬 Watch this step-by-step guide to replacing the sensor yourself.Why is it important to use a high-quality replacement sensor?
The crankshaft position sensor provides essential data for engine timing. Low-quality aftermarket sensors can have incorrect resistance or fail quickly, leading to the same symptoms you were trying to fix. Forum discussions among INFINITI owners strongly recommend using the OEM brand, Hitachi, to ensure a lasting repair.
Helpful Videos
Technical Specifications
OEM Part Numbers: 23731-4M50D
The sensor is located on the lower passenger side of the engine, at the junction with the transmission bellhousing. It is a 3-wire Hall effect sensor.
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.
- INFINITI M45: