Direct injection fuel injectors mounted in cylinder head, fed by high-pressure fuel rail (2000+ psi), six injectors total
Pins
2-pin connector
Idle Frequency
25 Hz
Timebase
2ms/div
Voltage Scale
20V/div
Trigger
5V, rising edge
Wiring
Red/Light Blue (12V power supply from fuel injector power relay), Black/White or various (PCM ground control circuit, varies by cylinder position)
Expected Voltage Range
At Idle
0V to 65V
At Higher RPM
0V to 65V
Expected Pattern
Initial peak voltage spike (50-65V) as injector opens against high fuel pressure, plateau at battery voltage during hold phase, then inductive kickback spike when PCM cuts ground
Known-Good Waveform
Direct injection waveform shows aggressive initial peak spike to 50-65V (peak-and-hold driver) lasting 0.2-0.3ms to rapidly open injector against 2000+ psi rail pressure. Hold phase settles to 12-14V for pulse duration of 0.8-2.5ms at idle. Inductive kickback at close reaches 45-60V with clean decay and minimal ringing. Current limiting creates distinct two-stage pattern.
Common Failure Patterns
Low or absent peak voltage (below 40V), weak or missing kickback spike
EcoBoost high-pressure direct injectors are prone to carbon buildup causing flow restrictions and misfires. Monitor fuel rail pressure with scan tool while viewing waveforms - should see 2000-2900 psi at idle. Compare all six injector waveforms simultaneously to identify failing units. Low-pressure fuel pump failures are also common, affecting injection timing.
Related Diagnostic Trouble Codes
P0200P0201P0202P0203P0204
Always confirm waveform data with your vehicle's OEM service manual before diagnosing.