ISX Fuel Actuator

[Rawze]

(09-13-2016 )bsiddle Wrote:  Afternoon everyone,

I run into a problem that I'm having no luck figuring out.

I have an ISX 871 that idles very rough. I know this because I have the same (same year model, year) motor in another truck.

So far I've checked all hose connections, changed the fuel shutoff value and changed, filters several times (been doing this for a while).

I started unplugging each actuator, one by one, and noticed a change in sound. It actually idled better with one unplugged than all plugged in.

Occasionally, the fuel delivery pressure light will come on, but it usually goes off within seconds. It does this even with the tanks completely full of fuel, so don't think it's a pickup tube. It also doesn't lack power, so I haven't changed any hoses. But, it will belo black smoke when you get into it hard.

Any thoughts?

It is likely you will find that your injectors have been cooked by the DPF system. i can't count the number of truck owners who run their trucks with partially blocked up DPF cans, check engine lights and regen lights coming on and off, etc... the cans half way blocked up,.. cooking their injectors out of their engines because the heat cannot escape the engine. I see it over and over, what you end up with is rough idle, leaky injectors, and if it gets bad enough,.. cracked pistons and bad head gaskets. -- All the while,,... blaming the engine instead of the fact that they were too damn cheap and lazy to keep the system running healthy via regular tune-up work and maintenance BEFORE the system started acting up. --- it is like everyone drives their truck with a damn blindfold on all the damn time and cry when the engine and systems start failing.

Follow the correct steps to find you problems and you will figure out what is wrong. Unplugging shi#t blindly will get you no-where and nothing but more confused!.


First of all,.. unplugging actuators will not do anything much towards troubleshooting any problems with it. The ECM gets confused and will do some strange, unreliable things when they are unplugged and then plugged back in while the truck is running. It can take up to several minutes for the ECM to re-enable them properly and/or set the injection mapping back right after it sees one has been disabled. it can really throw things off by a LOT and fool you every time into thinking there is problems ,.. Ironicly,.. just like you stated -- ESPECIALLY screw with your head when it comes to unplugging the the actuators for the back 3 injectors. -- YOU COULD UNPLUG actuators an a completely healthy truck, .. and very quickly come to the conclusion that there are problems with either the actuators or injectors every time!. I see ignorant idiot mechanics do this, and change thousands of dollars worth of parts, chasing ghosts!> I got a better idea -- Educate yourself and DON'T CHASE GHOSTS!


STOP UNPLUGGING ACTUATORS AND STOP GUESSING AT IT!!!--- YOU ARE WASTING YOUR TIME DOING IT THAT WAY!!!


FIRST thing you should do is verify your fuel pressure readings to ensure they are steady. This can be done in the Insite software (can be had from e-bay for about $350 or so).,

AFTER THAT!! --- DO AN INJECTOR LEAK TEST...





next.... IF IT PASSES AND THERE IS NO BUBBLES, do cut-out tests ...
<iframe id="lbry-iframe" width="560" height="315" src="https://lbry.tv/$/embed/insite-cylinder-cutout-test-by-rawze/745408fe6eb4b6196b74d576cf52cd1d420c03a3" allowfullscreen></iframe>


THEN FINALLY ... Check your Actuators...
http://rawze.com/forums/showthread.php?t...619#pid619

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