The Junk Bin Build app lets you test fuel injectors for a low cost.

If you mess around with cars long enough, you’ll realize two things: First, anything beyond the most basic repairs probably requires some sort of specialized tool, and second, those tools can be prohibitively expensive. But that doesn’t mean you’re out of luck, especially if you have a lot of junk and a do-it-yourself spirit, as is the case with older cars. Fuel injector test holder in this trash can It shows clearly.

[Desert Rat Racer]The company's test rig is designed to support four injectors simultaneously and test them under conditions as close as possible to those they will experience when installed. To this end, [Rat] He mounted a scrap intake manifold on a stand made from scrap wood and roadside metal. The pickle jar served as a reservoir for the test fluid—he wisely used mineral spirits as a safer alternative to gasoline—and a scrap electric fuel pump pressed into a scrap fuel rail, which distributed fuel to the injectors under test.

For testing, the injectors are connected to an electric injector tester, one of the few off-the-shelf components in this design. The fuel pump and injectors are powered by a 12-volt rail from an old computer power supply. Just being able to see the spray pattern is often enough to find a bad injector, but if a more quantitative test is indicated, each injector is placed over a cheap glass cylinder to catch the test fluid, and scraps of tape measure are used to measure the depth of the collected fluid. No fancy, expensive graduated cylinders are needed.

While we truly respect the breakthrough, [Desert Rat Racer]The concept of avoiding buying tactical gear is foreign to us. We understand the logic of not spending a lot of money on a disposable tool, but where is the fancy plastic case?