Guide to the 2003-2010 INFINITI M45 Camshaft Position Sensor
Fix common stalling, hard starting, and poor performance in your M45 by understanding this critical engine sensor.
- A failing camshaft sensor is a common cause of stalling, hard starts, and a Check Engine Light with codes P0340 or P0345.
- For best results and long-term reliability, use an OEM-supplier part like Hitachi. Cheaper aftermarket sensors are known to cause repeat failures.
- The M45 has two camshaft sensors located at the rear of the engine; it's wise to replace both at the same time.
- A recall (NHTSA ID: 03V455000) was issued for the 2003 M45 for this exact issue, highlighting it as a known problem.
Symptoms of a Failing Camshaft Position Sensor
When a camshaft position sensor in your M45 starts to fail, the signs are often hard to ignore. The car's computer may not know when to fire the spark plugs or inject fuel, leading to noticeable driving problems. You will almost certainly see the Check Engine Light come on, often with codes like P0340 or P0345 🎬 Watch: Diagnosing P0340 and P0335 codes on the VK45DE engine. stored in the computer.
Common Failure Symptoms:
- Engine Stalling: The engine may shut off unexpectedly while driving or when idling at a stop.
- Hard Starting or No Start: The engine may crank for a long time before starting, or it might not start at all.
- Poor Acceleration and Power Loss: Your M45 may feel sluggish and hesitant when you press the gas pedal.
- Rough Idling: The engine may shake or vibrate while the car is stationary.
- Reduced Fuel Economy: A bad sensor can cause the engine to use more fuel than necessary.
Choosing the Right Aftermarket Sensor
For critical electronic parts like a camshaft position sensor on a luxury vehicle, part quality matters. While many aftermarket options are available, owner experiences suggest that not all are created equal. Forum discussions for INFINITI and Nissan vehicles with similar engines often show frustration with cheaper, generic sensors that fail quickly or don't work correctly right out of the box.
Pro Tip: The VK45DE engine in the 2003-2010 M45 has two camshaft position sensors, one for each cylinder bank. While you may only have a code for one bank (e.g., P0340 for Bank 1), it is often recommended to replace both sensors at the same time to ensure balanced performance and prevent future issues, especially if they are original to the vehicle.
Brand Quality Tiers
- Tier 1 (OEM Supplier): Hitachi is the original equipment manufacturer for Nissan/INFINITI. Choosing a Hitachi sensor is the closest you can get to buying the part from an INFINITI dealer, ensuring the best possible fit, performance, and longevity. Many experienced owners and mechanics strongly recommend sticking with Hitachi to avoid problems.
- Tier 2 (Reputable Aftermarket): Brands like NGK, Beck Arnley, and Standard Ignition (SMP) have a solid reputation in the aftermarket. They often engineer their parts to meet or exceed OEM specifications. These can be a reliable choice if an OEM supplier part is not available or if you're looking for a balance between cost and quality.
- Tier 3 (Value-Oriented): Brands like Dorman, Walker Products, and other store brands offer a more budget-friendly option. While they provide a direct-fit replacement and often come with a warranty, community feedback suggests their performance can be inconsistent for this specific application. They may be a suitable short-term solution, but for long-term reliability, a higher-tier brand is often preferred.
Known Issues, Recalls, and TSBs
There was a significant recall (NHTSA Campaign ID: 03V455000) that included the 2003 INFINITI M45. This recall addressed improper solder joints on the circuit boards for both the camshaft and crankshaft position sensors, which could cause the engine to stall without warning. Dealers were instructed to replace the affected sensors. While this recall applied to the early Y34 generation, sensor issues are a known weak point across many Nissan and INFINITI models of this era. There are no other specific camshaft sensor recalls for the 2006-2010 Y50 generation M45, but a separate recall for the accelerator pedal sensor (NHTSA ID: 13V434000) can also cause stalling.
| Part Type | Estimated Cost |
|---|---|
| New OEM (Dealer) | $120 - $200+ per sensor |
| New Aftermarket (Provided Range) | $27.24 - $96.21 per sensor |
| Shop Labor | $80 - $150 |
Frequently Asked Questions (FAQ)
How many camshaft sensors does my 2003-2010 M45 have?
Your INFINITI M45 with the VK45DE V8 engine has two camshaft position sensors. There is one sensor for each cylinder bank (Bank 1 and Bank 2). Code P0340 refers to Bank 1 (passenger side) and P0345 refers to Bank 2 (driver's side).
🎬 See this step-by-step guide for replacing both camshaft sensors.Where are the camshaft sensors located?
The two camshaft position sensors are located at the back of the engine, near the firewall, on the top of each cylinder head cover. They can be difficult to access, especially the one on the passenger side, which may require removing the engine air intake ducting for better visibility.
Is this the same as a crankshaft position sensor?
No, but they are related and often confused. The M45 has two camshaft sensors and one crankshaft position sensor. While they all monitor rotating parts of the engine, they have different jobs. Interestingly, on some VK45DE engines, the camshaft and crankshaft sensors can be the same physical part, just mounted in different locations. A failure of the crankshaft sensor (Code P0335) can also cause stalling and no-start issues.
Can I replace this sensor myself?
Yes, this is a DIY-feasible job for someone with basic mechanical skills and tools. The main challenge is the tight access at the back of the engine. Each sensor is held in by a single 10mm bolt. The key is to have the right combination of socket extensions and patience to reach the bolts and disconnect the electrical connectors.
🎬 Watch this DIY walkthrough for accessing those tight sensor locations.What happens if I use a cheap sensor?
Using a low-quality sensor can lead to persistent problems. Owners frequently report that after installing a cheap aftermarket sensor, the check engine light returns, or the car continues to stall and run poorly, especially after the engine warms up. This often results in having to do the job a second time with a higher-quality part like Hitachi, costing more time and money in the long run.
Helpful Videos
Technical Specifications
OEM Part Numbers: 23731-AL61A 23731-AL61D 23731-4M50B 23731-JA11A
The VK45DE V8 engine uses two camshaft position sensors, one for each cylinder bank. They are typically located on the rear of the valve covers. The sensor is a Hall-effect type, held in by a single 10mm bolt, and uses a 3-pin electrical connector.
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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: