Knock Sensor – Fits Volvo Penta 4.3L/5.0L/5.7L Stern Drive Engines (Replaces 3854905)
Knock Sensor – Fits Volvo Penta 4.3L/5.0L/5.7L Stern Drive Engines (Replaces 3854905) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Knock Sensor – Fits Volvo Penta 4.3L/5.0L/5.7L Stern Drive Engines ...
Product Details
This Knock Sensor – Fits Volvo Penta 4.3L/5.0L/5.7L Stern Drive Engines (Replaces 3854905) is a direct replacement for Volvo Penta 4.3L, 5.0L, and 5.7L stern drive engines from 1994–2003. It monitors engine detonation (knocking) to prevent internal damage and helps the engine control unit maintain optimal performance and fuel efficiency.
This part serves as a direct interchange for Volvo Penta 3854905, Sierra 18-7679, and Mallory 9-33504.
- Features a direct bolt-on installation design.
- Monitors engine detonation to protect against engine damage.
- Engineered for use in marine gasoline applications.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Volvo Penta | 3854905 |
| Sierra | 18-7679 |
| Mallory | 9-33504 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This part is designed for specific Volvo Penta stern drive models. Please verify your engine is listed.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Volvo Penta | 4.3L | 4.3L | 4-Stroke | 1994–2002 | 3854905 | |
| Volvo Penta | 4.3GIJBYA | 4.3L | 4-Stroke | 1995–1996 | 3854905 | |
| Volvo Penta | 4.3GIJWTR | 4.3L | 4-Stroke | 1995–1996 | 3854905 | |
| Volvo Penta | 4.3GIPBYCCE | 4.3L | 4-Stroke | 1995–1996 | 3854905 | |
| Volvo Penta | 4.3GiPEFS | 4.3L | 4-Stroke | 1995–1996 | 3854905 | |
| Volvo Penta | 4.3GIPHUSCE | 4.3L | 4-Stroke | 1995–1996 | 3854905 | |
| Volvo Penta | 4.3GIPLKDCE | 4.3L | 4-Stroke | 1995–1996 | 3854905 | |
| Volvo Penta | 4.3GIPLKECE | 4.3L | 4-Stroke | 1995–1996 | 3854905 | |
| Volvo Penta | 4.3GIPNCACE | 4.3L | 4-Stroke | 1995–1996 | 3854905 | |
| Volvo Penta | 4.3GIPNCBCE | 4.3L | 4-Stroke | 1995–1996 | 3854905 | |
| Volvo Penta | 4.3GIPNCMCE | 4.3L | 4-Stroke | 1995–1996 | 3854905 | |
| Volvo Penta | 4.3GIPWTC | 4.3L | 4-Stroke | 1995–1996 | 3854905 | |
| Volvo Penta | 4.3GIPWTR | 4.3L | 4-Stroke | 1995–1996 | 3854905 | |
| Volvo Penta | 4.3GXi-A | 4.3L | 4-Stroke | 2000–2003 | 3854905 | |
| Volvo Penta | 5.0GXi-A | 5.0L | 4-Stroke | 2001–2002 | 3854905 | |
| Volvo Penta | 5.7Gi-A | 5.7L | 4-Stroke | 2001 | 3854905 | |
| Volvo Penta | 5.7GiI-A | 5.7L | 4-Stroke | 2001 | 3854905 | |
| Volvo Penta | 5.7GIINCCCE | 5.7L | 4-Stroke | 1995–1996 | 3854905 | |
| Volvo Penta | 5.7GIINCSCE | 5.7L | 4-Stroke | 1995–1996 | 3854905 | |
| Volvo Penta | 5.7GIPNCACE | 5.7L | 4-Stroke | 1995–1996 | 3854905 | |
| Volvo Penta | 5.7GIPNCBCE | 5.7L | 4-Stroke | 1995–1996 | 3854905 | |
| Volvo Penta | 5.7GIPNCMCE | 5.7L | 4-Stroke | 1995–1996 | 3854905 | |
| Volvo Penta | 5.7GIPNCSCE | 5.7L | 4-Stroke | 1995–1996 | 3854905 | |
| Volvo Penta | 5.7GLPNCS | 5.7L | 4-Stroke | 1995–1996 | 3854905 | |
| Volvo Penta | 5.7GSiI-A | 5.7L | 4-Stroke | 2000–2003 | 3854905 | |
| Volvo Penta | 5.7GXi-A | 5.7L | 4-Stroke | 2000–2003 | 3854905 | |
| Volvo Penta | 5.7GXi-B | 5.7L | 4-Stroke | 2000–2003 | 3854905 | |
| Volvo Penta | 5.7GXiI-A | 5.7L | 4-Stroke | 2000–2003 | 3854905 | |
| Volvo Penta | 5.7GXiI-B | 5.7L | 4-Stroke | 2000–2003 | 3854905 |
Technical Specs
- Product Type
- Knock Sensor
- Installation
- Direct bolt-on
- Fuel Type
- Gasoline
- Connection
- Wire harness connector with bolt mount
- Housing Material
- Metal
- Housing Color
- Black/metallic
- Dimensions
- 7.5 cm x 8.0 cm x 6.0 cm
- Weight
- 50g (0.11 lb)
- Fitting Type
- Threaded bolt mount
- Warranty
- 1 Year
- Other Technical Attributes
- Monitors engine detonation/knock
What’s in the Box
- 1 x Knock Sensor (3854905)
Installation Notes
- Disconnect the vessel's battery before starting work.
- Locate the existing knock sensor on the engine block. Note the wire routing.
- Carefully disconnect the electrical connector from the sensor.
- Using the appropriate wrench, unbolt and remove the old sensor.
- Clean the mounting surface on the engine block to ensure a solid connection.
- Thread the new sensor into place by hand, then torque it to the manufacturer's recommended specification. Do not overtighten.
- Reconnect the electrical harness securely.
- Reconnect the battery, start the engine, and check for any fault codes to ensure proper function.
Troubleshooting & FAQ
How do I know if my knock sensor is failing?
Common signs of a bad knock sensor include an illuminated check engine light, audible engine knocking or pinging (especially under load), reduced fuel economy, and decreased engine power or hesitation.
What happens if I don't replace a faulty knock sensor?
Ignoring a failed knock sensor can lead to severe engine damage over time. The engine's computer cannot retard timing to prevent detonation, which can damage pistons, rings, and bearings, leading to costly repairs.
Is this a direct fit for my specific Volvo Penta engine?
This sensor is designed for the Volvo Penta 4.3L, 5.0L, and 5.7L stern drive engines listed in the compatibility table. Please cross-reference your engine model and year with the provided list to ensure correct fitment.
Does this sensor require any special calibration?
No, this is a direct-fit component. As long as it is installed correctly and torqued to specification, the engine's control unit (ECU) will recognize and use its signal without requiring manual calibration.
OEM vs. Aftermarket?
This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.
Shipping speed & cost
We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.
Warranty & returns
Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.
Safety & Important Info
- Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
- This is an aftermarket replacement, not an OEM component.
- Professional installation is recommended for safety and performance.
About Sea Sierra
- Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
- Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
- Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.
Payment & Security
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