Idle Air Control (IAC) Motor – Fits Volvo Penta 4.3/5.0/5.7 GXI Engines (Replaces 3843751, 3857696)
Idle Air Control (IAC) Motor – Fits Volvo Penta 4.3/5.0/5.7 GXI Engines (Replaces 3843751, 3857696) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
Orders are typically processed within 1–2 business days.
U.S. orders usually arrive within 6–15 days, depending on stock location and destination.
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Idle Air Control (IAC) Motor – Fits Volvo Penta 4.3/5.0/5.7 GXI Eng...
Idle Air Control (IAC) Motor – Fits Volvo Penta 4.3/5.0/5.7 GXI Engines (Replaces 3843751, 3857696) is backordered and will ship as soon as it is back in stock.
Product Details
This Idle Air Control (IAC) Motor – Fits Volvo Penta 4.3/5.0/5.7 GXI Engines (Replaces 3843751, 3857696) is engineered for specific Volvo Penta 4.3, 5.0, and 5.7 liter GXI and related V6/V8 marine engines. As a key component of the electronic fuel injection system, it automatically regulates engine idle speed for smooth performance.
This part provides a direct interchange for Volvo Penta 3843751 and 3857696, Sierra 18-7705, and Regitar RMS002, ensuring broad compatibility.
- Installation: Designed for a direct bolt-on replacement.
- Connection: Features a multi-pin electrical connector for a secure factory fit.
- Function: Restores stable idle by precisely managing airflow.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Volvo Penta | 3843751 |
| Volvo Penta | 3857696 |
| Sierra | 18-7705 |
| Regitar | RMS002 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This component fits a wide range of Volvo Penta GXi, Gi, and OSi series engines. Verify your specific model against the list.
Compatibility has also been cited by aftermarket sources for several MerCruiser models, including the 350 MAG MPI and MX 6.2L MPI.
| Brand | Model | Rated HP | Stroke | OEM Part No. | Notes |
|---|---|---|---|---|---|
| Volvo Penta | 4.3GXi-B, 4.3GXi-BF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 4.3GXi-C, 4.3GXi-CF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 4.3GXi-D, 4.3GXi-DF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 4.3GXi-E, 4.3GXi-EF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 4.3GXi-F, 4.3GXi-FF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 4.3GXi-G, 4.3GXi-GF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 4.3GXi-J, 4.3GXi-JF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 4.3GXi-P, 4.3GXi-Q | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 4.3GXi-225-R | 225 | 4-Stroke | 3843751/3857696 | |
| Volvo Penta | 4.3Gi-200-R | 200 | 4-Stroke | 3843751/3857696 | |
| Volvo Penta | 4.3OSi-B, 4.3OSi-BF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 4.3OSi-C, 4.3OSi-CF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 4.3OSi-D, 4.3OSi-DF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 4.3OSi-E, 4.3OSi-EF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 4.3OSi-F, 4.3OSi-FF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 4.3OSi-G, 4.3OSi-GF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 4.3OSi-J, 4.3OSi-JF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.0GXi-B, 5.0GXi-BF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.0GXi-C, 5.0GXi-CF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.0GXi-D, 5.0GXi-DF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.0GXi-E, 5.0GXi-EF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.0GXi-F, 5.0GXi-FF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.0GXi-G, 5.0GXi-GF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.0GXi-J, 5.0GXi-JF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.0GXi-N | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.0OSi-B, 5.0OSi-BF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.0OSi-C, 5.0OSi-CF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.0OSi-D, 5.0OSi-DF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.0OSi-E, 5.0OSi-EF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.0OSi-F, 5.0OSi-FF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.0OSi-G, 5.0OSi-GF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.0OSi-J, 5.0OSi-JF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.7Gi-B, 5.7Gi-BF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.7Gi-C, 5.7Gi-CF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.7Gi-D, 5.7Gi-DF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.7Gi-E, 5.7Gi-EF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.7Gi-F, 5.7Gi-FF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.7Gi-G, 5.7Gi-GF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.7Gi-300-J, 5.7Gi-300-JF | 300 | 4-Stroke | 3843751/3857696 | |
| Volvo Penta | 5.7Gi-300-N | 300 | 4-Stroke | 3843751/3857696 | |
| Volvo Penta | 5.7GXi-C, 5.7GXi-CF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.7GXi-D, 5.7GXi-DF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.7GXi-E, 5.7GXi-EF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.7GXi-F, 5.7GXi-FF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.7GXi-G, 5.7GXi-GF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.7GXi-H, 5.7GXi-HF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.7GXi-J, 5.7GXi-JF | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | 5.7GXi-N | 4-Stroke | 3843751/3857696 | ||
| Volvo Penta | V6-200-A | 200 | 4-Stroke | 3843751/3857696 | |
| Volvo Penta | V6-225-A | 225 | 4-Stroke | 3843751/3857696 | |
| MerCruiser | 350 MAG MPI | 4-Stroke | Compatibility cited by FridayParts | ||
| MerCruiser | BLACK SCORPION SKI | 4-Stroke | Compatibility cited by FridayParts | ||
| MerCruiser | 377 SCORPION MCM & SKI | 4-Stroke | Compatibility cited by FridayParts | ||
| MerCruiser | MX 6.2L MPI | 4-Stroke | Compatibility cited by FridayParts | ||
| MerCruiser | 7.4L MPI (L29) | 4-Stroke | Compatibility cited by FridayParts | ||
| MerCruiser | 575 SCi | 4-Stroke | Compatibility cited by FridayParts |
Technical Specs
- Product Type
- Idle Air Control (IAC) Motor
- Installation
- Direct bolt-on replacement
- Fuel Type
- Gasoline
- Connection
- Multi-pin electrical connector
- Function
- Electronic fuel injection component that regulates idle speed
What’s in the Box
- 1 x Idle Air Control (IAC) Motor (3843751/3857696)
Installation Notes
- Disconnect the negative battery terminal to ensure safety.
- Locate the existing Idle Air Control motor, which is typically mounted on the throttle body.
- Carefully unplug the electrical connector from the IAC motor.
- Remove the mounting screws holding the old motor in place and gently remove it. Be careful not to drop any hardware into the engine.
- Clean the mounting surface and port on the throttle body to ensure a proper seal with the new part.
- Position the new IAC motor and install the mounting screws, tightening them to the manufacturer's recommended torque. Do not overtighten.
- Securely reconnect the electrical connector.
- Reconnect the negative battery terminal.
- Start the engine and allow it to run for several minutes. The engine's computer will relearn the idle position with the new motor.
Troubleshooting & FAQ
What are the signs of a failing IAC motor?
Common symptoms include an erratic or rough idle, engine stalling at low speeds, a high or low idle, and potentially a "Check Engine" light illuminating on your dashboard.
How can I confirm this part fits my specific engine?
The most reliable method is to match the part number from your old IAC motor to the numbers listed in our Part Number Matrix. Additionally, review the extensive Engine & Model Compatibility table to find your engine model and year.
Does this part require calibration after installation?
No special tools are required. After installing the new IAC motor, simply start your engine and let it run for a few minutes. This allows the Engine Control Unit (ECU) to perform a relearn procedure and automatically adjust to the new component.
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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