To Dennis and others interested in the mystery module on my 78 F-150. I found some notes that I made during the resto 4 yrs ago. The module in question is 1"x4"x5" black plastic and located behind dash on the "V" shaped steering column support bracket. The module has been identified on page 234 of the Haynes 73-79 Ford truck manual; #36054 (788),bottom schematic right side of page as the throttle actuator. Now this truck does not have an EGR valve or Cruise control. The module drives a vac. solenoid on the left valve cover which modulated a vac. diaphram/sol. on the Carb (2150).I had traced the wires out during resto. The wire colors match with the Haynes schematic and is wired as shown except substitute Vacuum solenoid for EGR Sol. on the drawing. I had attempted to draw out the circuit but never finished. I know the module senses pulses from the ign. coil and uses them to drive a power transistor in the module which drives the vac. sol. on the valve cover. Part Numbers of module is D7HF-14A608-AA. Part Number of circuit board is D7HF-9F 441-AA. I believe what is happening is the module senses and counts coil pulses and when the accelerator pedal is released suddenly the decreasing pulse frequency is sensed and causes the vacuum throttle positioner to allow the throttle valve to come back to idle slooowly to prevent stalling the engine when the pedal is released suddenly. (aka an electronic dash-pot). I suppose I am saying all this in hopes someone might have schematic diagram whereby I can fix this baby. Maybe I am just dreaming. Thanks anyone.......Terry.....

 

Terry, I just ran those numbers by my Ford parts manager and he says the Numbers are No Good. :-X23
I have to go out to the garage and find my OLD Number change-up books to see if the number changes up to something else.
Thanks, Just when I start getting some sleep
at night,this happens.
I'll be back !
Dennis

Oh....Please Don't Ask Me Any Tough Questions As:
"I'm Saving Up MY Memory For When I Develop Alzheimer's"






78 F-150 429CJ C6 ,Silver w/Explorer Pkge
641/2 Mustang,Pre-World's Fair Car #8092
64 Fairlane S/C waiting for a 390-4spd.
68-Mustang.Sunlit Gold 80,000 miles

 

Hi Terry,
I just home from the wreckers.
The manager friend of mine sent me home with this said part.
You're right about the numbers,they just Don't show up in the present Ford System and I can't find a change-up number in the book.

The one I have is stamped 8 Cyl,so I assume it has something to do with ignition like you said.
I'll be checking on this part for a while.


Dennis

Oh....Please Don't Ask Me Any Tough Questions As:
"I'm Saving Up MY Memory For When I Develop Alzheimer's"






78 F-150 429CJ C6 ,Silver w/Explorer Pkge
641/2 Mustang,Pre-World's Fair Car #8092
64 Fairlane S/C waiting for a 390-4spd.
68-Mustang.Sunlit Gold 80,000 miles

 

 

Sorry to bring this thread back from the dead, but i have this same exact module in my 82 f250. I also have the same electronically controlled dashpot on my carb. I'm trying to determine a way to test this module. From what I can tell it never does anything. I have never been able to verify that it works. The part number on mine is d7hf-9f441-aa. It's dated Mar 19 1982 and is also stamped 8 CYL. Any help or more info on this would be great! Thanks

 

Oh how almost 5 years can change things.

https://www.ford-trucks.com/forums/5...cker-help.html

 

ha ha...that was actually another post of mine! I'm trying to verify that information. The reason i'm not sure about the AC component is that there is no signal wire that would trigger that module from the AC contorols. It does seem that it is tied into a speed sensor. Any idea about that?? i havn't been able to find anythign else about it