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Mopar1973Man

APPS voltage Adjustment - Stopping the Myths!

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Great Write-up Michael, lot of problems reported on these forums are associated with this:smart::thumb1:

Tomorrow,..if i get a chance i want check voltage at PCM and then at the APPS and calculate the difference....

Richie

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Great Write-up Michael, lot of problems reported on these forums are associated with this:smart::thumb1:

Tomorrow,..if i get a chance i want check voltage at PCM and then at the APPS and calculate the difference....

Richie

Actually once again there is no reason to adjust the APPS at the PCM... PCM has no bearing on the engine... The only thing the PCM wants to see is throttle position for Auto Trans shift reason and it feed throttle information to the ECM for cruise control...

Still and all the ECM is more important to get the value right... Which is setting the APPS below the set on the tag... Anywhere below...

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Michael, I know.. I am just curious is to how much drop there is...as we discussed over the phone hhen i first put the DVM on pin#23 org/blk wire at PCM connector my voltage was 0.314 so thinking it was low compared to o.448 printed on tag on rear of APPS i ajusted to Aprox. .447-.448 @ the PCM and it made no improvement infact i think it may have been worse...i tinking that the .314 was real close to begin with if messured at APPS or ECM....:shrug: I need to recheck it anyway and use the wire @APPS to get it correct using your method:smart: Richie

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mike,

i am going to calibrate my tps today. checked my tps for the voltage and ther is not one on my new one. ther is on my old one. my new one came from blue chip diesel and is made by williams controls. ever heard of them before?

ripley

---------- Post added at 11:11 AM ---------- Previous post was at 11:09 AM ----------

by checking for voltage imean the sticker on the back like my old one has. my new one does not have one.

ripley

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mike,

i am going to calibrate my tps today. checked my tps for the voltage and ther is not one on my new one. ther is on my old one. my new one came from blue chip diesel and is made by williams controls. ever heard of them before?

ripley

---------- Post added at 11:11 AM ---------- Previous post was at 11:09 AM ----------

by checking for voltage imean the sticker on the back like my old one has. my new one does not have one.

ripley

Because the one you bought is a Timbo's APPS... You might want to go here for more details on calibration...

http://forum.mopar1973man.com/showthread.php/1527-Timbo-APPS

http://forum.mopar1973man.com/attachment.php?attachmentid=698

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well i'll be.

ripley

---------- Post added at 12:43 PM ---------- Previous post was at 11:31 AM ----------

my voltage resd .607. i turned the screw on the bell crank till the voltage rose and backed the screw off and the voltage never dropped below .607 no matter how far i turned it. my target was .595. ibacked the screw about two turns past .607 and no change. ican move the linkage that liitle bitn with my hand and the voltage does not change until it reaches the origanal position, then it starts to climb. should the voltage have not dropped more?

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There is no target voltage on the new sensor just turn the screw till the voltage start to rise then back off to it returns then back off additional 1/2 turn. Thats it... No voltage to adjust to...

To clear this up more... (The best I can)

The fact is that the stock APPS sensor is a rheostat yes. But it is set at a particual voltage to the electronic switch inside reports to the ECM if it at IDLE or THROTTLING. If the voltage rises above the voltage set on the tag the switch changes to THROTTLING. Then when the voltage drops BELOW this voltage on the tag then the ECM switches to IDLING. This means the APPS voltage is disregarded and idling software takes over.

NOW... The Timbo APPS... There is no set voltage tag because the switch for ON IDLE and THROTTLING is mechanical this means once the bellcrank gets to a particual angle THROTTLING starts regardless of voltage. So there is no voltage to adjust it just a matter of taking the slack out of the bellcrank.

So now you know why you DON'T set for EXACTLY the tag voltage because now it will constantly flip back and forth between IDLING and THROTTLING causing issues with exhaust brakes, high idle software, etc.

It not about the voltage its about the fact of the Idle Validation switch state...

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