Attention: TDR Forum Junkies 
petersonj
TDR MEMBER
Removing the Complete APPS Assembly From Engine.
First, and foremost, I was inspired to perform this modification by @Mace (a new member of the Mopar1973man site) who provided the idea - I never would have thought to do it on my own. I also want to thank him for providing the "how to do it " information as well as a list of parts.
Mace’s purpose of this modification was to free up some space in the engine compartment and to get the APPS into a better environment – inside the cab. As a result, his APPS mounting re-location required a complete APPS assembly which included an integrated throttle pedal. A mount would have to be fabricated and the old throttle pedal would have to be removed.
After thinking about this for a while, I wrote down what I wanted to accomplish - which was:
* I wanted the engine noise that was being transferred through the throttle cable into the cabin gone!
* I wanted the APPS throttle assembly removed from the engine because this was the source of the unwanted noise and vibrations that I heard and felt (throttle pedal) inside the cabin.
* I wanted to keep my fast idle solenoid
* I wanted to keep the adjustable throttle stop
* I wanted to keep the 45° sweep of the APPS
* I wanted to get the delicate APPS off of the pulsing, vibrating engine!
So, here is what I did. (I need to note here that this only works for a manual transmission truck because there is no cruise control connection or transmission cable connection the APPS assembly.)
There are no changes inside the cab. I just relocated the complete APPS throttle assembly to a place between the brake master cylinder and the oil dipstick tube. I fabricated a custom mounting bracket and used two existing bolts on the hydraboost / brake master cylinder unit for mounting the bracket.
This photo shows the custom fabricated mount and its new location.
Two more bolts and nuts and the throttle assembly is mounted.
With the use of Deutsch female and male two-pin connector harnesses, I lengthened the wiring to connect the ECM to the APPS.
Here is how much space that has opened up with the removal of the APPS assembly. The big aluminum mount on the left wasn’t yet removed when I took the photo.
Everything now is easily serviceable. The whole APPS assembly can be unbolted (either from the hydraboost or the APPS assembly mount) with just two fasteners. The unit can be lifted up and laid flat for throttle cable disconnect / replace. The APPS can be removed / installed without removing the APPS assembly. The idle stop and the fast idle can be adjusted with the engine running. The fuel filter is easy to remove / replace.
Now for the best news - the noise is gone! Completely absent! It doesn't matter whether or not my foot is on or off the throttle, or if cruise control is engaged or not. I didn't realize it until now, but that rattly noise was always there to some degree at every throttle position - including foot off the throttle.
Some other benefits - when I turn on the Fast Idle switch now, the tach goes to about 1150 rpm and is steady as a rock (used to float +/- 50 rpm). The tach is now rock solid at idle. The throttle is smoother with precise throttle control making gear shifting even more seamless. When coming off of cruise control, I can now make the transition seamless.
Shoulda done this about 393,000 miles ago!
- John
First, and foremost, I was inspired to perform this modification by @Mace (a new member of the Mopar1973man site) who provided the idea - I never would have thought to do it on my own. I also want to thank him for providing the "how to do it " information as well as a list of parts.
Mace’s purpose of this modification was to free up some space in the engine compartment and to get the APPS into a better environment – inside the cab. As a result, his APPS mounting re-location required a complete APPS assembly which included an integrated throttle pedal. A mount would have to be fabricated and the old throttle pedal would have to be removed.
After thinking about this for a while, I wrote down what I wanted to accomplish - which was:
* I wanted the engine noise that was being transferred through the throttle cable into the cabin gone!
* I wanted the APPS throttle assembly removed from the engine because this was the source of the unwanted noise and vibrations that I heard and felt (throttle pedal) inside the cabin.
* I wanted to keep my fast idle solenoid
* I wanted to keep the adjustable throttle stop
* I wanted to keep the 45° sweep of the APPS
* I wanted to get the delicate APPS off of the pulsing, vibrating engine!
So, here is what I did. (I need to note here that this only works for a manual transmission truck because there is no cruise control connection or transmission cable connection the APPS assembly.)
There are no changes inside the cab. I just relocated the complete APPS throttle assembly to a place between the brake master cylinder and the oil dipstick tube. I fabricated a custom mounting bracket and used two existing bolts on the hydraboost / brake master cylinder unit for mounting the bracket.
This photo shows the custom fabricated mount and its new location.
Two more bolts and nuts and the throttle assembly is mounted.
With the use of Deutsch female and male two-pin connector harnesses, I lengthened the wiring to connect the ECM to the APPS.
Here is how much space that has opened up with the removal of the APPS assembly. The big aluminum mount on the left wasn’t yet removed when I took the photo.
Everything now is easily serviceable. The whole APPS assembly can be unbolted (either from the hydraboost or the APPS assembly mount) with just two fasteners. The unit can be lifted up and laid flat for throttle cable disconnect / replace. The APPS can be removed / installed without removing the APPS assembly. The idle stop and the fast idle can be adjusted with the engine running. The fuel filter is easy to remove / replace.
Now for the best news - the noise is gone! Completely absent! It doesn't matter whether or not my foot is on or off the throttle, or if cruise control is engaged or not. I didn't realize it until now, but that rattly noise was always there to some degree at every throttle position - including foot off the throttle.
Some other benefits - when I turn on the Fast Idle switch now, the tach goes to about 1150 rpm and is steady as a rock (used to float +/- 50 rpm). The tach is now rock solid at idle. The throttle is smoother with precise throttle control making gear shifting even more seamless. When coming off of cruise control, I can now make the transition seamless.
Shoulda done this about 393,000 miles ago!
- John
