For car enthusiasts and those undertaking engine modifications, particularly converting older carbureted vehicles to modern fuel injection, the integration of aftermarket engine control units (ECUs) with OBD2 diagnostics is a frequent question. The ability to monitor engine parameters and log data via the standardized OBD2 protocol, familiar to many through smartphone apps and scan tools, offers significant advantages. This article explores the availability and capabilities of Aftermarket Obd2 Ecus, drawing upon insights from experienced automotive tuners and DIYers.
Understanding Aftermarket ECUs and OBD2
Aftermarket ECUs, also known as standalone ECUs, are programmable engine management systems designed to replace or supplement factory ECUs. They offer greater flexibility and control over engine parameters, crucial for modified engines or custom setups. OBD2 (On-Board Diagnostics II) is a standardized system for vehicle self-diagnostics and reporting, providing access to a wealth of engine and vehicle data through a universal connector.
The original question posed in a car enthusiast forum was straightforward: “Does such a thing exist?” – referring to aftermarket standalone ECUs with an OBD2 output. The user aimed to utilize existing OBD2-compatible apps for monitoring a carbureted car converted to throttle body injection. This highlights a core desire: to blend the advanced control of aftermarket ECUs with the user-friendly diagnostics of OBD2.
Aftermarket ECU Brands Offering OBD2 Output
The forum discussion reveals that the answer is yes, certain aftermarket ECU manufacturers do incorporate OBD2 output in some of their products, particularly in higher-end models. Here are some notable examples mentioned:
Link ECU and Haltech
Reputable brands like Link ECU and Haltech are confirmed to offer OBD2 capabilities in select ECUs. However, it’s important to note that this feature is generally found in their more advanced and consequently, more expensive product lines. For users seeking OBD2 compatibility, specifying this requirement when considering Link or Haltech ECUs is essential to ensure the chosen model includes this functionality.
MegaSquirt and MSLabs OBD Adapter
The MegaSquirt ECU, a popular open-source option known for its versatility and community support, can also be integrated with OBD2 through an adapter developed by MSLabs in Greece. This adapter bridges the MegaSquirt ECU (MS2 or MS3) via CAN bus and translates its data into standard OBD2 PIDs (Parameter IDs). Trackspeed Engineering also stocks these kits, expanding accessibility beyond custom-built MSLabs ECUs. It’s worth noting that while marketed as a wideband input solution, its OBD2 output functionality is a significant benefit for data monitoring.
Emerald K6 ECU
The Emerald K6 ECU is another example of an aftermarket ECU with OBD2 output. As mentioned in the forum, with the correct breakout connector and firmware, the K6 can output a range of OBD2 PIDs. These include essential engine parameters like water temperature, manifold pressure (MAP), RPM, road speed, ignition advance, air temperature, throttle position, lambda AFR, barometric pressure, and battery voltage. Furthermore, Emerald K6 extends OBD2 functionality with custom PIDs for parameters such as map switch position, gear position, coil-on-time, EGT (Exhaust Gas Temperature), and injector pulse widths, offering a richer data stream than standard OBD2 alone might provide.
OBD2 Data Logging and Considerations
The forum discussion also touches upon the practical aspect of OBD2 data logging with aftermarket ECUs. While the OBD2 output enables the use of numerous OBD2 readers and apps (like Torque for Android), it’s crucial to understand the limitations of generic OBD2 logging.
As pointed out, OBD2 logging speed can be relatively slow, particularly when attempting to record a large number of parameters simultaneously. This is a general limitation of the OBD2 protocol itself and not specific to aftermarket ECU implementations. For basic monitoring and less data-intensive logging, OBD2 via aftermarket ECU is perfectly adequate. However, for high-speed, comprehensive data acquisition, dedicated logging systems that interface directly with the ECU’s CAN bus or proprietary data outputs might be more suitable.
Despite the speed limitations, OBD2 output from an aftermarket ECU offers a significant advantage: accessibility. It allows users to leverage readily available and affordable OBD2 tools, including smartphone apps, for real-time monitoring and basic data logging, offering a valuable layer of engine insight without requiring specialized or expensive equipment.
DIY OBD2 Data Logging Solutions
For those interested in a more hands-on approach to data logging, the forum thread mentions open-source hardware options like Sparkfun OBD-II UART and CAN bus modules, along with Arduino platforms. These tools empower users to build custom OBD2 data logging solutions, potentially tailored to specific needs or integrated into custom dashboards or displays. While requiring programming and electronics knowledge, these DIY approaches offer flexibility and deeper control over data acquisition.
Conclusion: Aftermarket OBD2 ECUs – A Practical Solution
Aftermarket ECUs with OBD2 output provide a valuable bridge between advanced engine management and accessible diagnostics. While not universally available across all aftermarket ECU models and often found in higher-end systems, options from brands like Link ECU, Haltech, MegaSquirt (with adapter), and Emerald K6 demonstrate the feasibility and growing demand for this integration.
For users seeking to monitor their engine performance using standard OBD2 tools in conjunction with an aftermarket ECU, exploring these brands and specific models with OBD2 capabilities is highly recommended. Understanding the potential limitations of OBD2 logging speed is important, but for many applications, the convenience and accessibility of OBD2 integration with aftermarket ECUs offer a compelling solution. Further research into specific ECU models and their OBD2 implementation details is advised to ensure compatibility and meet individual project requirements.
