Duramax LLY - FICM / Injector Trouble / Misfire - Part 1
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Date: 2020-08-05
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Comments and reviews: 8
Fourty
I have watched a lot more videos trying to keep my junk on the road not as bad as this truck I glad to see you got the old Ford up and going again and if its anything like mine its usually just long enough to earn another check and sink that money into the truck. they might be junk but there mine junk and every now and then on a perfect day with the right wind and stars all aligned they will run like new just long enough to give me hope only to not start the following morning following with some choice words to the blue oval gods. but at least it's not a Dodge. what I am saying it's nice to see you didnt boot the ol Ford out on the Working man just trying live his version on the American Dream Keep up the great work the videos are awesome and have helped me out alot i know you spend a lot your time for mechanical challenged people like me i have broken more than i have fixed and its been kinda expensive but atleast i learned what i have already known blame everything on the Millenials it makes me feel smarter and it just feels good. let me know how to donate to your beer fund or for a new hat
Jeep + Dodge = JUNK! Keep the rubber side down J.
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I have watched a lot more videos trying to keep my junk on the road not as bad as this truck I glad to see you got the old Ford up and going again and if its anything like mine its usually just long enough to earn another check and sink that money into the truck. they might be junk but there mine junk and every now and then on a perfect day with the right wind and stars all aligned they will run like new just long enough to give me hope only to not start the following morning following with some choice words to the blue oval gods. but at least it's not a Dodge. what I am saying it's nice to see you didnt boot the ol Ford out on the Working man just trying live his version on the American Dream Keep up the great work the videos are awesome and have helped me out alot i know you spend a lot your time for mechanical challenged people like me i have broken more than i have fixed and its been kinda expensive but atleast i learned what i have already known blame everything on the Millenials it makes me feel smarter and it just feels good. let me know how to donate to your beer fund or for a new hat
Jeep + Dodge = JUNK! Keep the rubber side down J.
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Kevin
I think you were over thinking the injector operation a bit. The operation is similar to a low impedance peak and hold injector on a gas engine. The way it is done is a little different since the gas injectors ran off of 12v and the ground was what provided the current limiting. In this case, as with most diesel direct injectors, they need a huge spike in energy to open the injector initially. The FICM has a voltage boost circuit in it to open the injector with high voltage, but then the voltage is quickly reduced once the injector opens. Obviously if it continuously put 50v through 0. 1ohm, that's 500A. That vehicle would be a ball of flames quickly, but that level of energy isn't needed to keep the injector open, so the voltage input gets quickly reduced to hold the injector open. So, 50v peak from the voltage booster in the FICM opens the injector very quickly, then the voltage drops substantially to reduce the power consumption of the injector and hold it open.
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I think you were over thinking the injector operation a bit. The operation is similar to a low impedance peak and hold injector on a gas engine. The way it is done is a little different since the gas injectors ran off of 12v and the ground was what provided the current limiting. In this case, as with most diesel direct injectors, they need a huge spike in energy to open the injector initially. The FICM has a voltage boost circuit in it to open the injector with high voltage, but then the voltage is quickly reduced once the injector opens. Obviously if it continuously put 50v through 0. 1ohm, that's 500A. That vehicle would be a ball of flames quickly, but that level of energy isn't needed to keep the injector open, so the voltage input gets quickly reduced to hold the injector open. So, 50v peak from the voltage booster in the FICM opens the injector very quickly, then the voltage drops substantially to reduce the power consumption of the injector and hold it open.
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kain0m
Regarding the high voltage peak during the turn-on: I'd assume this is just a probe loop, picking up the current inrush (it seems like the output is just floating while the injectors are not pulsing. It wouldn't make sense to send 40+ Volts into a circuit that has a resistance of 0. 4 Ohms max. - that'd be 100+ Amps.
If I recall correctly, the power stage is shared between the four injectors, while the control wire is multiplexing the ground side.
Another small hint at the FICM: The code generated by unplugging #5 was different to the code from #3.
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Regarding the high voltage peak during the turn-on: I'd assume this is just a probe loop, picking up the current inrush (it seems like the output is just floating while the injectors are not pulsing. It wouldn't make sense to send 40+ Volts into a circuit that has a resistance of 0. 4 Ohms max. - that'd be 100+ Amps.
If I recall correctly, the power stage is shared between the four injectors, while the control wire is multiplexing the ground side.
Another small hint at the FICM: The code generated by unplugging #5 was different to the code from #3.
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That
I got into Ford, Chevy/Isuzu diesel because I discovered there was plenty of money to be made on these poor trucks messed up by questionable modern emissions systems that plague otherwise alright motors with consistent problems.
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I got into Ford, Chevy/Isuzu diesel because I discovered there was plenty of money to be made on these poor trucks messed up by questionable modern emissions systems that plague otherwise alright motors with consistent problems.
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Steven
Holy Seagull poop! That was amazing. And I'm not so sure we can do it, unless we have the right equipment and your diagnostic coconut! Fabulouis video, just fabulouis. I bow to the Master.
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Holy Seagull poop! That was amazing. And I'm not so sure we can do it, unless we have the right equipment and your diagnostic coconut! Fabulouis video, just fabulouis. I bow to the Master.
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Alex
Anyone know how to reset the PCM TCM. My battery is went dead, after a jump start my speedometer is reading double my actual speed. I'm trying to avoid the dealer they want 290 to reset it.
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Anyone know how to reset the PCM TCM. My battery is went dead, after a jump start my speedometer is reading double my actual speed. I'm trying to avoid the dealer they want 290 to reset it.
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Derek
Sounds like a bad capacitor for number 3 power from the driver, that's why you have voltage but not the big drop. Voltage is going thru the capacitor but it is not storing enough energy.
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Sounds like a bad capacitor for number 3 power from the driver, that's why you have voltage but not the big drop. Voltage is going thru the capacitor but it is not storing enough energy.
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Paul
Duramax Diesel. an Isuzu diesel - - - - manufactured by lower valley bottom knuckle dragging family incest genetic aberrations in Moraine, (south of Dayton. but not by much) Ohio.
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Duramax Diesel. an Isuzu diesel - - - - manufactured by lower valley bottom knuckle dragging family incest genetic aberrations in Moraine, (south of Dayton. but not by much) Ohio.
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