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marvelouzone
New Member

7 Posts

Posted - 07/03/2016 :  7:21:18 PM  Show Profile  Visit marvelouzone's Homepage  Reply with Quote
Hello all. I have a 2002 international 4300 DT466. Just purchased a few weeks ago, when purchased I suspected a few bad injectors, had 357,XXX on dash, had a miss, hard start w/knock when cold... Had injectors tested 5 out of six where bad.. So i replaced injectors with rebuilt/reman ones. Changed oil, oil filter, and fuel filter

After bleeding fuel system, truck started right up cold, but I noticed it still had a miss, upon trying to drive it, it lacked a lot of power very bad. At this point I didn't have a scanner to scan for codes.. truck continued to start for days, just no power, ordered scanner(nexiq) used servicemaxx to get codes, got dtc 525.. upon reading I noticed that rarely is the idm itself the issue, but normally a wiring/clean power issue.. I checked all the known issues, and noticed that all connectors and fuse holders had been changed or removed all together.. I did find bad battery in the process, and replaced. I have not been able to locate ecm relay. Is it in the fuse box? cec relay?

With KOEO standard test passes, injector test brings up dtc525, if I run that same test with injector harness unplugged at valve cover I get 513 and 514 as expected, but no 525. So my question is should I be looking at injector side of harness for problem, or is it still probably a power issue? When truck was starting I was able to verify that all 6 injectors were firing.. just wondering what I really should focus on? is it possible that IDM was really dying causing my misfire in the first place, and now its really dead and does need to be replaced?

my idm is integrated with em, if it is bad do they sell bottom boards for these models as well?

Edited by - marvelouzone on 07/03/2016 7:23:54 PM

JoeHEB1
Advanced Member

498 Posts

Posted - 08/18/2016 :  11:36:03 AM  Show Profile  Visit JoeHEB1's Homepage  Reply with Quote
Try the MAP sensor located on the valve cover/intake manifold. It cured my low power issue on my exact DT466.
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RonF
Top Member

867 Posts

Posted - 08/19/2016 :  05:25:57 AM  Show Profile  Reply with Quote
Also, a bad air intake sensor, (IAT) or manifold air temperature sensor (MAT) can cause a low power issue, although I'm not sure if a 2002 would have that on it or not.

US Army retired CMBT
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eddo
Advanced Member

USA
311 Posts

Posted - 08/19/2016 :  10:51:31 AM  Show Profile  Reply with Quote
Did you check the wiring for the injectors when you had them out? I had a pinched wire once, inside the valve cover that caused a 525 and a miss.

perhaps during reinstall?
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RonF
Top Member

867 Posts

Posted - 08/19/2016 :  12:13:06 PM  Show Profile  Reply with Quote
quote:
Originally posted by eddo

Did you check the wiring for the injectors when you had them out? I had a pinched wire once, inside the valve cover that caused a 525 and a miss.

perhaps during reinstall?



Been there, done that.

US Army retired CMBT
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jeeptjken
Senior Member

147 Posts

Posted - 08/24/2016 :  06:34:31 AM  Show Profile  Reply with Quote
the idm and ecm power relays are zip tied to the harness that comes up near the steering shaft I have had a few enclosed inside the loom as well they should have purple wires to them as well

How did you get the gosinta in the whatchamacallit
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