For drivers of classic and pre-OBD2 vehicles, monitoring fuel efficiency can often feel like a guessing game. Modern cars come equipped with MPG (miles per gallon) displays, providing real-time feedback to help you drive more economically. But what if your beloved older car lacks this feature? Fortunately, thanks to the ingenuity of the open-source community, there’s a solution: the MPGuino. This DIY project allows you to add an MPG display to your pre OBD2 car, giving you valuable insights into your fuel consumption and driving habits.
What is MPGuino and Why Retrofit an MPG Display?
The MPGuino, born from the opengauge.org project, is a customizable, Arduino-based MPG gauge designed specifically for vehicles without the standard OBD2 (On-Board Diagnostics II) port found in newer cars. Before OBD2 became mandatory in the mid-1990s, vehicles lacked a standardized way to access engine data electronically. This meant no easy way to plug in a modern MPG display.
Retrofitting an MPG display to your pre-OBD2 car offers several benefits:
- Real-time Fuel Efficiency Monitoring: See exactly how your driving style impacts fuel consumption in real-time. This immediate feedback is crucial for learning to drive more efficiently.
- Save Money on Gas: By understanding your MPG, you can adjust your driving habits to maximize fuel economy and reduce trips to the gas station.
- Understand Your Vehicle Better: An MPG display provides another data point to understand your engine’s performance and identify potential issues that might be affecting fuel efficiency.
- DIY Fun and Customization: The MPGuino is a DIY project, offering a rewarding experience for car enthusiasts and those who enjoy tinkering with electronics. It’s also highly customizable to fit your specific needs and vehicle.
Key Features of the MPGuino DIY MPG Gauge
The MPGuino project is packed with features, making it a powerful and versatile MPG display solution:
- Multiple Display Screens: View instant MPG, current trip data, tank MPG, and more, all configurable to your preferences. You can choose jumbo-sized MPG readouts for easy viewing or detailed screens with comprehensive trip information.
- High Precision Fuel Tracking: The MPGuino is designed for accurate fuel usage and distance calculations, giving you reliable MPG readings.
- Arduino-Based Flexibility: Built on the Arduino platform, the MPGuino benefits from the ease of use and extensive community support of Arduino. This makes it relatively accessible even for those new to microcontrollers.
- Advanced Code Concepts (For the Tech-Savvy): The MPGuino code incorporates sophisticated programming techniques, including an event scheduler for efficient task management, microsecond timing for precision, function pointers, object-oriented design, and interrupt handling for real-time data capture from injectors and speed signals.
- Non-Consecutive LCD Data Pins: Allows for flexible wiring configurations.
- CPU Utilization and Free RAM Monitoring: Provides insights into the MPGuino’s performance.
While the underlying code is advanced, the project is designed to be accessible, with a focus on “cut and paste” simplicity for loading the code onto your Arduino.
Building and Installing Your MPGuino
While detailed step-by-step instructions are available at the MPGuino wiki, here’s a general overview of what’s involved in building your own MPG display:
- Gather Components: You’ll need an Arduino board, an LCD screen, and a few other electronic components. The project can be built from scratch for around $20 if you source components carefully.
- Wiring: Follow the provided wiring diagrams to connect the components. The diagrams are designed to be Arduino-friendly, simplifying the wiring process.
- Code Upload: Download the MPGuino code from the opengauge.googlecode.com repository and upload it to your Arduino board.
- Installation in Your Car: Install the MPGuino in your car and connect it to the necessary signals, such as injector pulses and a speed signal, to measure fuel consumption and distance.
Alt text: Dual MPGuino MPG displays installed in the dashboard of a classic car, showcasing a practical application of adding MPG monitoring to a pre-OBD2 vehicle.
Alt text: Wiring diagram illustrating the connections between the Arduino, LCD, and other components for the MPGuino MPG gauge project, emphasizing the DIY aspect of adding MPG display to older cars.
Alt text: Early prototype of the MPGuino DIY MPG gauge, demonstrating the evolution and development process of creating a fuel efficiency display for pre-OBD2 vehicles.
Alt text: MPGuino MPG gauge constructed from scratch, highlighting the cost-effectiveness and DIY nature of adding fuel consumption monitoring to a pre-OBD2 car for under $20.
Drive Smarter and Save Fuel with MPGuino
Adding an MPG display to your pre-OBD2 car with the MPGuino project is a fantastic way to modernize your classic ride and gain valuable insights into your fuel consumption. It’s a rewarding DIY project that can help you drive more efficiently, save money on gas, and deepen your understanding of your vehicle. Explore the resources provided by opengauge.org and the MPGuino community to embark on this exciting and practical automotive upgrade.
Further Resources:
- MPGuino Source Code: http://opengauge.googlecode.com/svn/trunk/mpguino/mpguino.pde
- MPGuino Wiki (Installation & Details): http://ecomodder.com/wiki/index.php/MPGuino
- opengauge.org: http://opengauge.org
