A customer of ours recently started having start up issues. He had sent his injectors back to the manufacturer and they did a “flow test” and determined they were “fine”. Not TRUE!!!
Here you can see that one injector failed the pressure test. As fuel pressure drops AFTER the engine is shut off (in this simulation), this one injector is dripping fuel into the cylinder. That leaves unburned fuel in the cylinder and makes the next start up more difficult. This video was the best of four back to back to back tests we did. The previous tests showed cylinder 1 and cylinder 4 dripping, with cylinder 4 dripping more in the previous tests.
Flowing testing alone and saying the injectors are “fine” is like tuning an engine for only full throttle. It’s only a small piece of the puzzle. There’s a lot more to proper tuning and proper injector testing. We’ll clean these injectors up and see how they hold up afterwards. Hopefully it clears up the start up issue that just started happening.
