96 7.3. Bad IDM right ??
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96 7.3. Bad IDM right ??
So this morning my truck wouldn’t start, glow plugs are are working and I barrowed a scanner from work and my icp pressure is 1000 psi cranking and 54% ipr duty cycle. But the scanner doesn’t do function test so I checked the IDM and got 12v going to it and back probed the 2 put put power wires #23 and #24 And only got 4.5 v out of one and 0 v on the other wire while cranking. Got the same number when I back probed the connectors at the valve cover. So bad IDM correct ??
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A number of conditions have to be met before the injectors are fired. HPOP pressure at the ICP, RPM and Sync with the CPS to name a few. I'm not convinced that you have proven the IDM bad. Did you shake it and see if it has water in it? Did you check the connectors at the valve covers for burned pins?
The guys over in the powerstroke forum know this cold. I would be over there if I were you. Did you get their no-start flow chart?
https://www.ford-trucks.com/forums/forum170/
The guys over in the powerstroke forum know this cold. I would be over there if I were you. Did you get their no-start flow chart?
https://www.ford-trucks.com/forums/forum170/
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No Start Flowchart:
https://drive.google.com/file/d/0Byb...1qRU1VVGc/view
You didn't mention fuel pressure?
https://drive.google.com/file/d/0Byb...1qRU1VVGc/view
You didn't mention fuel pressure?
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The buzz test would be good if your scanner will do it. You can watch the pulse width too, I think the pulse width changes when the injectors are firing. You can pull a valve cover and see if the injectors are squirting a little oil when they fire.
https://oregonfuelinjection.com/serv...gnostics/#1994
Check these: If the battery voltage is low the IDM won't fire. Maybe the same for 5v too.
4. Injectors bad; Injectors with high miles on them can fail to operate cold. If correct PW displays on cranking you can remove the valve cover and watch the oil spill discharge, every injector should discharge oil when pulsed by the IDM during cranking. If no pulse of oil then the injector isn't activating and injecting fuel into the cylinders. Running several buzz tests cold will sometimes free up the injectors. This is typical in a high mileage situation with inadequate engine oil changes.
Check these: If the battery voltage is low the IDM won't fire. Maybe the same for 5v too.
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I
my fuel pressure gauge dosnt fit my truck but when I push the Schrader valve while cranking is shoots right out so thats atleast enough pressure to feed the pump. And if it were injector issues I’d be loosing a cylinder or two not all 8. I took off the IDM-120 and found that someone has already messed with it. All siliconed together by a 6th grader and missing all the screws for the circuit board
my fuel pressure gauge dosnt fit my truck but when I push the Schrader valve while cranking is shoots right out so thats atleast enough pressure to feed the pump. And if it were injector issues I’d be loosing a cylinder or two not all 8. I took off the IDM-120 and found that someone has already messed with it. All siliconed together by a 6th grader and missing all the screws for the circuit board
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Nope that’s what I’m thinking. And I’m getting no voltage on one bank and only 4.5 volts on the other. Should be 48 volts
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6.0 is forty something volts. The 7.3 is 100 some odd volts.
Check me on all of this. I want to learn it but you know how it is... So many toys, so little time.
Injector info was posted in support of IDM questions. When does the system ask the IDM to fire? You have to know you are meeting these conditions before you can say the IDM is not working. Maybe it's not being asked to work. Maybe there is a clear cut test for the IDM. Closest thing I know of is a buzz test. If you throw IDM codes on a buzz test it might tell you something. The injectors spurting oil shows they are being fired by the IDM.
Check me on all of this. I want to learn it but you know how it is... So many toys, so little time.
Injector info was posted in support of IDM questions. When does the system ask the IDM to fire? You have to know you are meeting these conditions before you can say the IDM is not working. Maybe it's not being asked to work. Maybe there is a clear cut test for the IDM. Closest thing I know of is a buzz test. If you throw IDM codes on a buzz test it might tell you something. The injectors spurting oil shows they are being fired by the IDM.
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You may be right on the voltage spec it I thought it was 48 volts but I work on many other diesels so I may have gotten the spec wrong. But the IDM needs signal from the pcm to fire and the pcm won’t give that command until it sees at least 500 psi from the icp and a high enough rpm speed from the cmp as well as have good strong battery’s.
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Somewhere I saw mention of a signal that excites the IDM but I can't for life of me remember what it was. And just like you said, I could be thinking of another system. The signal from the cam sensor is an input. The other one, the one I'm not sure of, I think is from the computer to the IDM.
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https://www.ford-trucks.com/forums/8...stuck-low.html
This might be what I was thinking of. Maybe it doesn't excite the IDM.
Know anyone with a good IDM you can try?
Pin 96 CID cylinder identification
Pin 95 FDCS Fuel Delivery Control Signal 650-3600rpm
Pin 48 EF Electronic Feedback digital electronic frequency
Those are the lines I was thinking of. That and $1 will get you a cup of coffee. That was from the coffee table book.
http://www.powerstrokediesel.com/index/419
This might be what I was thinking of. Maybe it doesn't excite the IDM.
Know anyone with a good IDM you can try?
Pin 96 CID cylinder identification
Pin 95 FDCS Fuel Delivery Control Signal 650-3600rpm
Pin 48 EF Electronic Feedback digital electronic frequency
Those are the lines I was thinking of. That and $1 will get you a cup of coffee. That was from the coffee table book.
http://www.powerstrokediesel.com/index/419
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No I tried asking around for a IDM and the crappy part is I use to have a extra one then sold it. But I’m going to order a new one online and on Monday I’m going to see if I can barrow a better scanner. The shop one sucks so most guys buy there own where I work