Injector Balance ?

[icemanjc1]

It's weird, I was complaining about my #4 injector running at 1.6mm3 on a balance, logged it today now #6 is running around 3.2mm3 at idle, then I put it in gear and it goes down to average with the other 5. Wondering about the negative readings also...

[FUBAR]

Mine acted the same when I drove truck today off idle. But at least I think I got the rates figured out on how they work.

[hunterhd590]

How do I do a balnce test. I can't find the option anywhere? Is there a step by step anywhere?

[FUBAR]

There is no balance test. Only a kill test. We cannot do it with EFILive (yet?) You can view what your balance rates are via ScanTool. Select one of the pid groups that have them in it and log it. One thing I've noticed on every truck is at idle one injector will always read higher but balance out once a little throttle is given.

-Andrew

[comnrailpwr]

There is no balance test. Only a kill test.

-Andrew

How exactly do we kill individual injectors Andrew. I haven't even looked into it yet and am sure I can figure it out but I didn't know this was available for the 5.9.


Jake

[DoghouseDiesel]

Here is one thing to understand with the injectors when it comes to flow.

The factory spec is 24 lpm, but the tolerance is 1 - 3 lpm. So if you have stock nozzles, you can have a pretty wide variance in actual flow.

Most aftermarket nozzles that are sold as a balanced set are within 1 lpm or less of each other.

As for the kill test, its not available in the EFILive software, but it is a function you can do with the StarScan or StarMobile. Its one of THE best tools for quickly isolating a bad injector.

[comnrailpwr]

Thanks for the info. Always wondered what the factory specs of nozzle flow was.

I didn't think efilive could kill individual injectors. I agree with it being the best way to find bad stix.

Jake

[cumminsDK]

my understanding of balance rates is this, they are adjustments to the commanded fuel value for each injector to get the same cylinder contribution from each cylinder at idle, log balance rates on a duramax and you will see that when you barely move the pedal without changing idle rpm that the engine will begin to shake and the balance rates will go to 0 on the scantool, so a negative number would mean that that injector is flowing more fuel and the ECM is subtracting fuel on that cylinder to get an even contribution from all cylinders