Petrol Injectors

This capture is from a 2006 VW TFSI, direct injection turbo charged engine. This is a differential coupling and you can see it resembles the common rail diesel injector pattern. The control unit contains capacitors that provide the high voltage used to operate the injectors, usually 2 capacitors for a 4 cylinder engine.

Petrol direct injection electromagnetic solenoid injector voltage

This waveform image shows the detail of a common, multipoint petrol injector, mounted in the inlet manifold. (Indirect injection or manifold injection). This was taken from a 2006 2.0 Mazda.

Common solenoid petrol injector voltage and current

This next waveform set, show a sample taken from a direct injection petrol BMW (N43), which uses piezo injectors.  The first image shows a full cycle of cylinder No.1.  I have used a maths channel to show the actual injector opening signals, as the other voltage signals can be confusing.  They are the ghost signals from the driver circuit in the ECU and completely normal.  Unfortunately I was unable to get a current clamp in place to sample current.  But, as you will see, I have managed to show what the current pattern would look like, from the ground side voltage drop.

Siemens Piezo Injector voltage in a 720 degree cycle
Siemens Piezo Injector close-up with volt drop of ground

This next image is a capture of the same type of petrol injector as above, only this one has a current sample also.  It plainly illustrates how the current signal mimics the volt-drop shown in the ground voltage signal above.

Piezo petrol injector voltage and current
Siemens Piezo High pressure direct petrol injection injector sample.