Hello everyone,

Gradually browsing through this great site, I read here about the Adario method.

Here's what I think is a similar tip -- it might be here already -- probably is.

If you have only a single current probe you can -- if the injection system uses low ohm injectors and an external resistor pack -- see "parade" traces by clamping the common feed wire.  You get to see all injector currents on one trace.  Fine.

But if you want to see injection in relation to another event, you need to identify each injector.

Sure you can use a second current clamp, or probe for injector voltage, or pick up an ignition event or a rotational sensor, but they all need a channel -- you might only have two -- and then you might have to search for a book to relate the injection event via the inlet opening time etc etc.

But how about if you clamp both the common feed, and the Injector #1 feed as well.

You get a trace like this GIF.  

This shows the six cylinder injection parade with #1 at double amplitude due to the clamp seeing its current twice. (You have to run the wires in "opposite" directions, otherwise you'd see nothing for Inj #1)  I know the firing order is 1, 4, 2, 5, 3, 6.

You can use the same technique to see (and identify) just a few cylinders, for example clamping on #2 and #5, to see whether the ECU controls each bank separately.  In this case you don't have to run a wire through twice, because you know from the firing order that #2 opens just before #5.  (see second GIF)

Regards to all,
Ed

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Here's the second GIF.
The first of each pulse pair is Inj #2, the middle cyl on the rear bank.
The following pulse is Inj #5, the middle cyl on the front bank.

Car is 1994 Rover 2.7 V6 with Honda PGM-Fi on C27A engine.
Ed

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Welcome and thanks for the tip.  I have used two current probes at once it can be handy at times like comparing two door lock actuators.  One thing to be aware of in my experience triggering off a inductive current probe is not as stable as triggering directly off voltage but it could be something I am doing wrong.  

One other cool tip on this is there are several components on one power feed all the components can be seen at once and on  chryslers it is possible to turn on and off each component with a scan tool KOEO.  Its not the same as running but if just looking for a difference it can be helpful.

Sam