Is there a locost way of checking that the injectors are recieving the correct voltage?

I tried sticking a multimeter on each injector in turn... I only get around 6.5V at each injector... but this might be because the pulse is so small...

What I am trying to do is workout why I have a misfire at idle... injectors or engine management system are the only options left following an engine rebuild which has not fixed the issue..

think an osciloscope would show the peak voltage. multimeter would only show an average i think

Yep, only a scope will tell you the true voltage.

Iirc the injectors on my honda VFR had permanent 12v to one pin and were switched to ground by the ECU on the other.

Might be worth checking how they are switched to make sure you measuring the right thing - sorry if Im a step behind you here.

Geoff

quote:

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Iirc the injectors on my honda VFR had permanent 12v to one pin and were switched to ground by the ECU on the other.

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Needs a scope, some DMMs will give you the duty cycle.

Quick simple check is to use a Noid light --- with experience it can tell you a lot.

The fact that all of them appear to be giving the same average voltage with a multimeter suggests that they are all getting some sort of feed..

I assume an injector is a logic device in that it only fires if there is enough voltage, it wont "half fire" if the voltage is too low?

Most injector problems are due the injector getting gunged up, this would show up more at wide open throttle.

If the engine passes a compression test (or better a leak down test) then the most likely cause of an idle speed single cylinder misfire is a coil pack/plug/plug lead.
However first check the inlet and exhaust manifolds for leaks.

so far I have:

replaced coilpack
replaced HT leads
Replaced plugs

Remove the head, reground valves, replaced camshaft and rockers

Installed with new inlet/exhaust gasket and head gasket..

And the misfire still persists...

Its very noticeable at idle, but at around 3000 RPM it becomes les noticeable for the most part...

Its almost like the timiing advance at idle is out...

I really have no idea where to look next...