4
Turn ignition on and check for leaks. If no leaks are detected
proceed with tests.
The best way to understand how the FirstLook
®
Fuel Injection Sensor works
is to start with a known good engine. See how the injectors work at both
idle and during the 1500 RPM load test. Next disable an injector and run the
same test. Always remember injector problems can also be caused by a bad
electrical driver. It is just as important to know the electrical condition of
your injectors as it is to know their mechanical condition. Current ramp
testing of the fuel injector electrical system is the best way to verify proper
electrical condition. An engine with oversize fuel rails can cause you to see
two different sets of patterns. The injectors closest to you will appear to have
different waveforms than the injectors on the opposite side of the engine.
Remember what you are looking for is a repeatable pattern. The Nissan
fuel rail below notes this type of waveform. The firing order here is 1-2-3-
4-5-6. You will see 1, 3, 5 appear differently than 2, 4, and 6. This is a
normal condition on many cars. The bad injector is marked between the
cursers. See
www.senxtech.com
for more.