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MAP Sensor – Fits Volvo Penta, OMC, MerCruiser 4.3L-8.2L (Replaces 3850396, 864856A1)

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You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).

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Product Details

This Manifold Absolute Pressure (MAP) Sensor – Fits Volvo Penta, OMC, MerCruiser 4.3L-8.2L restores crucial engine data for optimal performance. It is designed as a direct-fit replacement for V6 and V8 EFI gasoline engines from Volvo Penta (1994–2007), OMC (1994–1998), and MerCruiser (1993–2007).

It provides a reliable aftermarket cross-reference for Volvo Penta 3850396, OMC 3850396, MerCruiser 864856A1, and Sierra 18-7684.

  • Engineered as a direct OEM replacement for straightforward installation.
  • Specifically for gasoline EFI engines with single point injection systems.
  • Features a standard electrical 3-pin connector for a secure connection.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Brand Part Number
Volvo Penta 3850396
OMC 3850396
MerCruiser 864856A1
Sierra 18-7684
Aftermarket AM3850396

Engine & Model Compatibility

Confirm your engine model/year in the table below.

This sensor fits a wide range of Volvo Penta 4.3L to 8.2L GI, GL, GS, and GXi series engines manufactured between 1994 and 2007.

Compatible with OMC V6 and V8 EFI engines from 1996 to 1998, including various 4.3L, 5.0L, 5.7L, 7.4L, and 8.2L models.

Fits numerous MerCruiser 4.3L, 5.0L, 5.7L, 350, 454, 502, 7.4L, and 8.2L EFI and MPI engines from 1993 to 2007.

Brand Model Rated HP Stroke Years OEM Part No. Notes
Volvo Penta 4.3GI, 4.3GL, 4.3GS series 160-320 4-Stroke 1994–2001 3850396 Multiple model variants
Volvo Penta 4.3GXi-A 225 4-Stroke 2000–2001 3850396
Volvo Penta 5.0GI, 5.0GL, 5.0GS series 220-250 4-Stroke 1994–2002 3850396 Multiple model variants
Volvo Penta 5.0GXi-A 270 4-Stroke 2001–2002 3850396
Volvo Penta 5.7GI, 5.7GL, 5.7GS series 215-280 4-Stroke 1994–2002 3850396 Multiple model variants
Volvo Penta 5.7GXi-A/B, 5.7GXiI-A/B 270-320 4-Stroke 2000–2002 3850396
Volvo Penta 5.8FSI series 380 4-Stroke 1995–1996 3850396
Volvo Penta 7.4GI, 7.4GL, 7.4GS series 310-405 4-Stroke 1994–2000 3850396 Multiple model variants
Volvo Penta 8.2GS series 415 4-Stroke 1995–2000 3850396
Volvo Penta DPX385X, DPX415X series 302-415 4-Stroke 1996–2000 3850396
OMC 43F series (V6) 4.3L 4-Stroke 1996–1998 3850396
OMC 432, 434 series (V6) 4.3L 4-Stroke 1996–1998 3850396
OMC 50FB, 502B series (V8) 5.0L 4-Stroke 1997–1998 3850396
OMC 572B, 574B series (V8) 5.7L 4-Stroke 1996–1998 3850396
OMC 57FA, 57FC, 57FD series (V8) 5.7L 4-Stroke 1996–1998 3850396
OMC 744D, 744E, 744F series (V8) 7.4L 4-Stroke 1995–1997 3850396
OMC 74FE, 74FF, 74FG, 74FH, 74FJ series (V8) 7.4L 4-Stroke 1995–1998 3850396
OMC 82FC series (V8) 8.2L 4-Stroke 1998 3850396
MerCruiser 4.3L V6 EFI engines 4.3L 4-Stroke 1994–2007 864856A1 Various models including Alpha/Bravo
MerCruiser 5.0L V8 EFI engines 5.0L 4-Stroke 1993–2007 864856A1 Various models including Alpha/Bravo
MerCruiser 5.7L V8 EFI engines 5.7L 4-Stroke 1993–2007 864856A1 Various models including Alpha/Bravo
MerCruiser 350 MAG EFI 350 4-Stroke 1994–1997 864856A1 Various configurations
MerCruiser 350 MAG MPI 350 4-Stroke 1995–1997 864856A1 Various configurations
MerCruiser 454 EFI Gen V/VI 454 4-Stroke 1994–1998 864856A1
MerCruiser 454 MAG MPI 454 4-Stroke 1996–1998 864856A1 Gen VI
MerCruiser 502 EFI/MPI 502 4-Stroke 1993–1998 864856A1 Gen V/VI
MerCruiser 7.4L MPI 7.4L 4-Stroke 1995–1997 864856A1 Gen V/VI
MerCruiser 8.2L MPI 8.2L 4-Stroke 1996–1997 864856A1 Gen VI
MerCruiser Scorpion 377 377 4-Stroke 1997–2004 864856A1
MerCruiser Black Scorpion 350 MAG 350 4-Stroke 1996–2001 864856A1

Technical Specs

Product Type
Manifold Absolute Pressure (MAP) Sensor
Installation
Direct OEM replacement
Fuel Type
Gasoline EFI
Connection
Electrical 3-pin connector
Housing Material
Plastic with metal components
Housing Color
Black
Dimensions
11.5 × 10.0 × 7.5 cm (4.53 × 3.94 × 2.95 inches)
Weight
50 g (1.76 oz)
Other Technical Attributes
Used on single point injection EFI systems

What’s in the Box

  • 1 x MAP Sensor (3850396/864856A1)

Installation Notes

  1. Disconnect the negative battery terminal to ensure safety.
  2. Locate the MAP sensor, which is typically mounted directly on the intake manifold.
  3. Carefully disconnect the electrical harness from the sensor.
  4. Unscrew the mounting bolt(s) holding the sensor in place and gently remove it.
  5. Clean the mounting surface to ensure a proper seal with the new sensor.
  6. Position the new MAP sensor and tighten the mounting hardware to the manufacturer's recommended torque. Do not overtighten.
  7. Securely reconnect the electrical connector.
  8. Reconnect the negative battery terminal.
  9. Start the engine and check for a smooth idle and ensure the check engine light is off.

Troubleshooting & FAQ

How do I know if my MAP sensor is failing?

Common signs of a faulty MAP sensor include a rough idle, poor fuel economy, engine hesitation or stumbling during acceleration, and an illuminated check engine light with corresponding fault codes.

Where is this sensor located on the engine?

The Manifold Absolute Pressure (MAP) sensor is almost always mounted on the intake manifold of the engine, allowing it to measure the pressure (vacuum) inside.

Can I use this on a multi-point injection (MPI) engine?

This sensor is primarily specified for single point injection (TBI/EFI) systems. While some MPI models are listed as compatible, it is crucial to verify your OEM part number (864856A1 or 3850396) before ordering, as many MPI systems use a different sensor.

What happens if I don't replace a bad MAP sensor?

A failing MAP sensor provides incorrect data to the engine control unit (ECU), which can lead to a rich or lean fuel mixture. This can cause increased emissions, reduced engine power, poor fuel mileage, and potential long-term damage to the catalytic converter.

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.

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