For car enthusiasts looking to boost the performance of their Mitsubishi Lancer, engine swaps can offer a significant power increase. Among the popular options, the 4G64 engine stands out as a robust and readily available choice. This guide delves into the intricacies of performing a 4G64 engine swap in a Lancer, with a particular focus on OBD2 compatibility and considerations.
Understanding the 4G64 Engine and OBD2 Compatibility
The 4G64 is a 2.4-liter inline-four engine from Mitsubishi, found in vehicles like the Eclipse and Galant. Known for its larger displacement compared to the Lancer’s stock engines, it offers a substantial increase in torque and horsepower, making it an appealing upgrade. Crucially, for vehicles equipped with OBD2 (On-Board Diagnostics II) systems, ensuring compatibility is paramount for maintaining diagnostic capabilities and emissions compliance.
When considering a 4G64 swap, especially for OBD2-equipped Lancers, it’s essential to understand that the engine itself is inherently OBD2 compliant from its original applications (typically model years 2000 onwards). However, the integration into a different vehicle chassis, like a Lancer, requires careful attention to wiring, sensors, and the Engine Control Unit (ECU) to ensure all OBD2 functionalities are retained. This includes the ability to read diagnostic trouble codes (DTCs), monitor engine parameters, and ensure emissions systems are functioning correctly.
Essential Parts for a 4G64 OBD2 Swap into a Lancer
Embarking on a 4g64 Obd2 engine swap necessitates gathering a comprehensive list of parts. Below is a detailed breakdown, drawing from successful swaps, to guide you through the necessary components:
Engine Components:
- 4G64 Engine (2.4L): Sourced from a 2000-2005 Mitsubishi Eclipse or Galant. Note the cam reluctor differences between 00-01 and 02+ models, which may require adjustment.
- Intake Manifold: The stock 4G64 intake manifold is generally used, though Outlander cast aluminum manifolds are a durable upgrade to address cracking issues common in stock manifolds.
- Exhaust Manifold: Stock 4G64 manifolds are compatible with 4G63T flange patterns, allowing for aftermarket options like Evo 8 or 2G Eclipse exhaust manifolds.
- Injectors: Stock 4G64 injectors are typically sufficient for this swap.
- Alternator and Power Steering Pump: Utilize the stock 4G64 alternator and power steering pump along with their respective brackets for mounting.
- A/C Compressor: 4G94/4G64 A/C compressors are interchangeable; ensure you obtain the correct bracket for 4G64 block mounting.
- MAF Sensor: A 501 Eclipse MAF sensor is required for proper air flow measurement.
- Motor Mount: The engine-side motor mount from the 4G64 is necessary, but custom brackets will be needed for chassis mounting.
- Radiator Hoses: Use a stock Eclipse lower radiator hose (trimmed by 1 inch on each end) and the stock Lancer upper radiator hose.
- Heater Hose: Approximately 14 inches of 5/8 heater hose will be needed for heater hose replacement.
- Coil Packs & Spark Plug Wires: Factory Lancer coil packs can be used, but one spark plug wire may be too short. Consider 4G64 coil packs if available.
- Valve Cover Gasket & Oil Pan/Gasket: Replacement of these gaskets is often advisable during an engine swap, especially if the donor engine’s condition is unknown.
Transmission Components:
- K5M422F6ND Transmission (5-speed): This 3G Eclipse 5-speed transmission is a compatible option.
- Transmission Mounts: The front and rear brackets from the Eclipse transmission are not needed; reuse the factory Lancer brackets. The top transmission mount (left motor mount) from a 2000-2005 Eclipse is required.
- Slave Cylinder: Obtain the slave cylinder from the Eclipse transmission, including the banjo bolt and fitting.
- Lancer Differential: Swap the stock Lancer differential into the Eclipse transmission as Lancer axles are not compatible with the Eclipse differential.
- Lancer Drive Shafts (Axles): After the differential swap, stock Lancer axles can be used.
- Starter: The Eclipse starter must be used with the 4G64 engine and Eclipse transmission.
Wiring and ECU Considerations for OBD2 Integration
Maintaining OBD2 functionality hinges significantly on proper wiring and ECU management. Key aspects include:
- Stock Lancer Wiring Harness: Reuse your stock Lancer wiring harness to simplify integration with the car’s existing systems.
- Sensor Clips: Acquire 4-inch wire clips with plugs for the crank angle sensor, throttle position sensor (TPS), and power steering pressure sensor from a compatible Mitsubishi vehicle for easier wiring adaptations.
- ECU: An 03 Mitsubishi Lancer Evolution 8 ECU (part number MN132874) is highly recommended. This ECU is OBD2 compliant and can be flashed to disable the immobilizer and adjust sensor configurations using a 1.3u Tactrix cable and software like EvoScan. Using an Evo 8 ECU ensures robust OBD2 diagnostics and tuning capabilities post-swap.
Addressing Potential OBD2 Error Codes (CELs)
After a 4G64 OBD2 swap, encountering Check Engine Lights (CELs) is not uncommon initially. Based on documented swaps, some typical OBD2 error codes and solutions include:
- P0123 (TPS High Input): Often due to incorrect wiring of the Throttle Position Sensor. Verify and correct TPS wiring based on wiring diagrams.
- P0113 (IAT High Input): Indicates a high input from the Intake Air Temperature sensor. This is often resolved by ensuring proper sensor connection and circuit integrity.
- P0107 (MAP Circuit Low Input): Relates to the Manifold Absolute Pressure sensor circuit. Check MAP sensor connections and wiring.
- P0455 (Evap System Large Leak): May occur if EVAP system plugs are not extended properly during the swap. This might require extending emissions plugs or reprogramming periphery codes within the ECU to manage EVAP system expectations.
Performance and OBD2 Monitoring After the Swap
Post-swap, the 4G64 engine provides a noticeable performance increase. While specific dyno results vary, expect improved torque and horsepower figures. MPG might slightly decrease compared to the original 4G94 engine, as noted in some swaps (around 28 mpg vs. 33 mpg in a Lancer with stock components).
OBD2 system becomes crucial for monitoring the health and performance of the swapped engine. Tools like EvoScan, used with the Tactrix cable, allow for data logging and real-time monitoring of engine parameters, coolant temperatures, and identifying any new OBD2 error codes that may arise. This diagnostic capability is invaluable for maintaining the engine and optimizing performance after the 4G64 swap.
Conclusion
Performing a 4G64 OBD2 engine swap into a Mitsubishi Lancer is a complex but rewarding upgrade for those seeking enhanced performance. By carefully sourcing the required parts, paying close attention to wiring and ECU compatibility—especially regarding OBD2 systems—and addressing potential error codes, enthusiasts can successfully integrate this powerful engine while retaining essential diagnostic functionalities. This conversion not only boosts engine power but also provides a platform for further performance tuning and modifications, all while staying within the parameters of OBD2 compliance for modern vehicle diagnostics.
References:
- rpmruffryders’ 4G64 Swap Post on evolutionm.net
- Limitless.co.nz (Tactrix Cable Source)
- Youtube Video of 4G64 Swap
- Dyno Sheet (Post 93 on Page 7 of EvolutionM Thread)
