I've been riding motorcycles for over 10 years. Like many other motorcycle enthusiasts I do my own maintenance, from chaining oil to adjusting valves. After seeing other people make DIY digital vacuum gauges I wanted to make one for my own use. Digital Vacuum Gauge is a nifty DIY project for the car/motorcycle enthusiast to help keep their engine throttle bodies/carburetors in sync.

The project is completely opensource. The eagle design, board layouts and source code is all available on sourceforge.

Functionality

The gauge is powered by a 9 volt battery. The LCD screen incorporates a back light. The functionality of the digital vacuum gauge is configured through the onscreen menu. The menu is accessed by pressing the MODE/CAL button.

The four pressure sensors can be calibrated to run in absolute pressure mode or relative to atmospheric pressure mode. The vacuum read out can be displayed in kPa, PSI, inHg or mmHg. The display can be set to show numerical values or draw bar graphs. The amount of digital filtering can also be configured.

The pressure sensors should be used with 3mm or 1/8" vacuum tubing. Below is a video walking through the menu. A short press moves through the menu options and a long press will select that option.

More details on assembly are on the instructables page. (Follow the documentation link on the right)

This product contains a PCB, Programmed Microcontroller and all the parts necessary to build the kit. Options are available for assembling the surface mount components and hole through components.