Building our own PCM and FICM (or how to get pilot injection back)
Senior User
Joined: Jun 2003
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From: Okanagan Valley, BC, Canada
Originally Posted by ZBeeble
If you think about it, the FICM, at 4100 RPM is firing the injectors 16400 times per second for regular injection and 32800 times per second for pilot injection.
More Turbo
Joined: Dec 2003
Posts: 534
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From: Park County, CO
Originally Posted by ZBeeble
Now... back to the beginning. The PCM and the FICM are tightly integrated. Without more information, I can't tell you if reprogramming or replacing the FICM alone would make pilot injection work. Likely, the PCM program changed somewhat when PI was turned off in the FICM because the power parameters would change.
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Senior User
Joined: Apr 2004
Posts: 319
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From: Oshawa/Ontario/Canada
Originally Posted by ssls6
I would guess that Pilot Injection was turned off because the injectors could not respond fast enough when the oil was thick (mechanical limitations). Your probably right about the 1800 rpm cap being a result of PCM/FICM (electrical) limitations. Keep in mind that it is an assumption that the electrical limitation is a result of a low clockrate. The clockrate of the chips may be more than adequate for the sensor response time or position encoders. I can promise you the sensors & encoders cost a lot more than the semiconductors.
In terms of sensor accuracy and electrical limitations, that's all up in the air ... but several knowledgable people have let on that PI is a power of logic failing. It's also true that more powerful logic can achieve sub resolution accuracy with sensors.
An interesting approach that hit me as I was typing this would be to make the FICM a variable clockrate ASIC design where the clockrate was generated by the CPS input --- such that the program (and the problem) might seem more static. Something to ponder.
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Senior User
Joined: Apr 2004
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From: Oshawa/Ontario/Canada
Originally Posted by ssls6
I would guess that Pilot Injection was turned off because the injectors could not respond fast enough when the oil was thick (mechanical limitations). Your probably right about the 1800 rpm cap being a result of PCM/FICM (electrical) limitations. Keep in mind that it is an assumption that the electrical limitation is a result of a low clockrate. The clockrate of the chips may be more than adequate for the sensor response time or position encoders. I can promise you the sensors & encoders cost a lot more than the semiconductors.
. But... don't forget that there's no reason we couldn't choose other injectors as an "option" for our system. Really, when you have the source, you can do anything ."Use the Source, Luke"
Senior User
Joined: Jun 2003
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From: Stockton, CA.
According to the shop manual that I downloaded from motorcraft.com,for my 2003 6.0. Pilot injection is controlled by the PCM. The PCM monitors the (EOT) engine oil temp. and the engine speed to enable the (PI Mode) When the (EOT) is grater than 50 C but less than 110 C
and the RPM is less than 800 PI mode is active
and the RPM is less than 800 PI mode is active
Last edited by cdtruckn; May 10, 2004 at 10:33 PM.
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Joined: May 2004
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Originally Posted by canuck999
Sorry mate, can't quite follow your math here!
The injectors fire on 4 cylinders for every revolution; at 4100RPM (68.333 revolutions per second), that would equate to 273.333 firings per second, not 16400.
The math has some problems, the rest I cannot comment on. Interesting topic though.
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Senior User
Joined: Apr 2004
Posts: 319
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From: Oshawa/Ontario/Canada
Originally Posted by nlhintz
4000RPM = 4000 revolutions per minute = 66.667 revolutions per second = 15 msecs per revolution (not 250 usecs).
The injectors fire on 4 cylinders for every revolution; at 4100RPM (68.333 revolutions per second), that would equate to 273.333 firings per second, not 16400.
The math has some problems, the rest I cannot comment on. Interesting topic though.
The injectors fire on 4 cylinders for every revolution; at 4100RPM (68.333 revolutions per second), that would equate to 273.333 firings per second, not 16400.
The math has some problems, the rest I cannot comment on. Interesting topic though.
Still, someone who knows about diesel engines has to step up to this project to make it viable.
Laughing Gas
Joined: Nov 2003
Posts: 900
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From: PHOENIX
Sounds like a great idea for you computer gurus! How about making it so I can hook up a laptop like in fast and the furious. 
Has anyone done anything like that yet?
I know on some of the newer fuel injected motorcycles you can reprogram with a laptop. Why not on superdutys?
Has anyone done anything like that yet?
I know on some of the newer fuel injected motorcycles you can reprogram with a laptop. Why not on superdutys?
Freshman User
Joined: Mar 2004
Posts: 39
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From: Mt. Airy, Md.
PI Flash>Predator>CD>Website>Anyone-who-wants-this-flash?-
Greetings!
I've been following this thread for a bit now.....am also concerned
with the lack of pilot injection even though my 6.0 CC just came
off the assembly line.
I suppose it gets into proprietary areas, but wouldn't it be feasible
to download someone's PI-enabled flash onto a Predator, then to
a CD and then to a website to anyone could get it and reflash
their truck with it?
Seems like it would work in principle, but maybe distributing this
would be a no-no....any ideas?
BTW, I have all ten fingers and toes crossed over this truck!
PSD 6-.-oh!
I've been following this thread for a bit now.....am also concerned
with the lack of pilot injection even though my 6.0 CC just came
off the assembly line.
I suppose it gets into proprietary areas, but wouldn't it be feasible
to download someone's PI-enabled flash onto a Predator, then to
a CD and then to a website to anyone could get it and reflash
their truck with it?
Seems like it would work in principle, but maybe distributing this
would be a no-no....any ideas?
BTW, I have all ten fingers and toes crossed over this truck!
PSD 6-.-oh!
Last edited by PSD Six-Point-Oh!; May 11, 2004 at 05:28 PM. Reason: Misspelling
Senior User
Joined: Jun 2003
Posts: 401
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From: Stockton, CA.
I'm looking into this but ford pulled a good one.
1st, before thy disabled pilot inj. the pcm was not OBD II compatible, Just WDS compatible.
That is y thy had the recall flash (03E03 or October flash) that made the PCM compatible and also disabled P/I .
So If you find a truck with P/I working the predator won't interface with it.
1st, before thy disabled pilot inj. the pcm was not OBD II compatible, Just WDS compatible.
That is y thy had the recall flash (03E03 or October flash) that made the PCM compatible and also disabled P/I .
So If you find a truck with P/I working the predator won't interface with it.
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Senior User
Joined: Apr 2004
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From: Oshawa/Ontario/Canada
Originally Posted by clockgod1
I have a 2004 build Excursion and the Pilot Injection works fine. I'm also running a predator with my truck with no problems with any interface.
Cargo Master
Joined: Jun 2003
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From: Carlsbad, California
I thought that the pilot injection was pricipally put in there to reduce noise.
Beyond a certain RPM and road speed other noise contributors begin to dominate and removal of PI is not going to be noticeable from an audible point of view.
Is there another performance reason for PI like improved mileage or power output? In otherwords, beyond making the truck quieter at idle and low speeds, why would all this effort be worthwhile?
Beyond a certain RPM and road speed other noise contributors begin to dominate and removal of PI is not going to be noticeable from an audible point of view.
Is there another performance reason for PI like improved mileage or power output? In otherwords, beyond making the truck quieter at idle and low speeds, why would all this effort be worthwhile?
