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Throttle shaft assembly

954 Views 8 Replies 2 Participants Last post by  bigfish95971
Im having a hard time locating a kit or ....
My throttle shaft / bell crank has play in it enough to drop a half of volt sending my apps in low signal CEL.
If can rock the throttle up and down and physical see the voltage drop.
Is there a kit that replaces the bearing or. Any one else ever deal with this?
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Is the is at idle? What is it normally and when it drops, measured on what plug terminal?
The electrical should not change idle voltage becasue of a loose bushing in the Bellcrank assembly.
drops exactly .27 volts from the factory .503 . I own a spare apps sensor . it does this with both sensors. There is no doubt its he bearing in the bell crank thats causing it.
500$ is a tuff pill to swallow over a 5$ part. Ill see if I can press it out and buy a new one I guess
When the senor on back of the bell crank is properly adjusted to around .5v it should not be able to drop below that. It is not to be adjusted with the set screw on the throttle crank. That is just a throttle cable stop to eliminate slack in the cable.
You adjust the sensor by loosening the two screws slightly and rotating the sensor to get between .500 and .529v on pin #3. It is quite sensitive when adjusting. That is the same as your idle validation voltage. That tells several systems the truck is at idle. Then when it starts to move up in voltage with pedal input it accelerates the truck and tells the trani and other things it is doing so.
So adjust the sensor properly and then see what it does.

Don't believe what you read about it not being adjustable on the back. That is from Chrysler trying to get you to buy the whole assembly from them.

PS this as you describe has not been a problem for anyone else I know of.
Its a failed bearing . This happens very often on ppump truck.
I know how to properly adjust the sensor properly and it is. Its pouring here or I would take a video. Now remember how sensitive the sensor is.
At this point in time my bearing inside my bell crank has slop in it. Like any other bearing that can fail with time. After open the throttle fully a few times the rod will slightly move or manipulate its self. The truck even jumps 200 or so rpm thinking im moving the throttle. After the rpm jumps 200 rpm the only way to get it to come down is shut the truck down . And I verified this with my digital volt meter with all my cables disconnected. I push the throttle shaft on the bell crank back in aligning it again the volts come back to .503 . Whats wrote exactly on my apps sensor and start the truck and its back to idle condition. I verified this with 2 apps sensors.
The bearing in the throttle shaft on the bell crank needs to be replaced.
P Pump? I thought we were talking about a standard 01 VP truck. You have not said otherwise. But if it still has the same APPS bell crank and sensor on the block for a 98.5 to 02 what I said still applies. The sensor output ill not drop below idle of .5 volts if is properly adjusted on back with the loosened screws. That is the built in electronically stop point for voltage regardless of what the crank is doing. Idle and idle validation signals can't drop below that .5XX setting. Now above that when throttle is applied, slop at that point could very well jump around.
If it is the standard crank and apps it sounds like someone has installed a sensor at the bottom of its rotation and then tried to adjust the idle voltage with the stop screw on the bell crank. This is not the correct way to adjust the apps idle voltage. The screw is just to adjust cable slack before taking up acceleration.

So what exactly is your setup. Pump? APPS year, brand APPS.
Pictures? Is the culprit bearing a ball bearing or bushing?
We are talking about my 01. I understand it all applies thats why I mentioned the ppump having similar problems. If ppump bell cranks can wear, why couldn't a vp44 do the same if they are so similar. No one tried to adjust the apps with the set screw ever not once.
I adjusted it right properly. Back to .503 because prior to that it would fall under volt and set off a check engine light giving me a dead pedal . Its the ball bearing being the shaft in front of the apps. Im not going to dismantle my truck in the rain for a picture. I know whats wrongs with it Im telling you the bearing is worn and has play in it sending my sensor reading askew. There is no doubt about it.
I asked about a replacement bearing and you seem to be hung up on the fact if my bearing went bad. It did there isnt a question about if it did or didnt.
Do you have or know of a part number to replace the bearing on the shaft in the bell crank?
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