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Drive by wire diesel

CaseyS

Well-Known Member
Messages
755
Location
Louisiana
Proof of concept on this is complete. I mounted the stock throttle body off to the side of the fuel filter. A cable is threaded through the throttle plate and clamped to the throttle lever on the 4bt.

Did a short test drive tonight and it gets itself down the road. The throw right now is a little non linear but functional. The throttle gets to about 60% before it faults. I think there is too much resistance. Next step is to remove the circular return spring on the throttle and use a softer linear spring attached to a forward point.



 

CaseyS

Well-Known Member
Messages
755
Location
Louisiana
Theoretically, once I crack the nut of traction control, the ecu will override throttle input and modulate torque, just like it would on the I5. Secondly, once I clear all the transmission fault codes, this should all me to run the factory cruise control. BOOM!
 

06 H3

a.k.a. "The Jackal"
Messages
9,506
Location
Meridian, ID
WOW awesome thinking out of the box! Working out all the little things is what makes a great build into an awesome one.
 

06 H3

a.k.a. "The Jackal"
Messages
9,506
Location
Meridian, ID
So you took disconnected the throttle cable from the pedal in the cab. Hooked up the drive by wire setup so the computer thinks it's factory then as the OEM throttle body opens it pulls the cable to open the 4bt throttle but around 60% if fails due to the resistance on the flap?

Before it fails does your reduced power go away?
 

4speedfunk

Well-Known Member
Messages
4,250
Location
Tardville
Sounds good except for the theory about throttle over-ride. I think there may be more to it than just throttle...like ignition timing.. Since you don't really have an ignition system...that might be a real challenge. Also what about the 5-cyl's VVT? I don't have a clue on how to fake those signals.

So do you think you could make an adapter to mount the GM throttle plate to the Cummins intake?
 

CaseyS

Well-Known Member
Messages
755
Location
Louisiana
I've had the throttle body plugged back in for several weeks now. I just tossed it in the intake box out of sight. It has been running in there literally just flapping in the wind to my throttle inputs. My throttle was still connected via cable input. This cleared the "reduced power message, but did not clear the traction control and stability system messages. I still have codes thrown associated with the transmission that it doesn't like, so I will need to get some tuning software and disable those to get closer to getting this thing in line. Also right now the cruise does not engage so the trans codes have that locked out as well.

So..yes, the drive by wire has been working with no faults over the last few weeks. So the last two days, I fabbed a real mount for the throttle body and rigged it up to do some actual work. Now that I put some physical load on the throttle plate, it objects after a certain point. This seems like it will be a fixable condition though. More tuning today.
 
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CaseyS

Well-Known Member
Messages
755
Location
Louisiana
Man this thing is slicker than owl snot. Disconnected the spiral spring under the throttle and went down to Lowes and bought a few springs. Fabbed up an external bracket to anchor on end of the spring and tried a few until I got the right feel and enough spring force to return back to idle properly. It now goes to wot with no faults. The throttle still produces most of its movement over the last half of foot movement. I have a fix in mind to help change the throw profile for a little more natural feel.

Other than needing a little more foot movement, it drives much closer to stock now. Much softer pedal feel and less vibration transmitted back up through my foot.

I think I will leave the cable in place. If anything ever fails, reverting back to the cable takes about 5 minutes. I have the final linkage stored in my console for emergencies.



Now I need to clean up all my wiring and make everything pretty. I need to find a real cable end as well to make it more secure.
 

RamRod

Well-Known Member
Messages
3,914
Location
AB, Canada
Looks like you could use a cable end for bike brake cables, super cheap and no special tools to crimp on, just some side cutters at a half squeeze


Sent from my iPad using Tapatalk
 

CaseyS

Well-Known Member
Messages
755
Location
Louisiana
Looks like you could use a cable end for bike brake cables, super cheap and no special tools to crimp on, just some side cutters at a half squeeze


Sent from my iPad using Tapatalk

Funny, that's what that cable is, a mountain bike brake cable. I used to have a dozen or so of the crimp ends floating at the bottom of my bike toolkit, but I couldn't find any the other night.

This morning I remapped my shift points to better match the pedal profile. Shifts a lot better and doesn't hang as long before the 2-3 shift.
 
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