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  #16  
Old 06-10-2011, 09:10 AM
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black wire i have 1.4ohms

so basically my tps is good right?


Have to say no, however not real clear how you tested it yet. You did disconnect the TPS harness connector, tested sensor resistance with it off correct?

The manual I have shows em as,

Brn-Wht = vref
Gry-wht = tp
Gry-red = sig-rtn

i installed it correct with setting it on and rotating till the screw holes line up and tighten them.

To adjust (91 and up) loosen screws, connect negative probe to the terminal with the gray/red wire and the positive probe to the terminal with the grey/white wire. rotate sensor with the ignition key "on" until the output reads 1.0 volt. Tighten screws recheck voltage.

Sounds like your in the ball park far as that goes though has .09-4.21v with a steady increase to wot and decrease to closed position. your within spec there.

orange wire has 5.05v be just a hair high, that .05v very small amount yea and might just be a slight error in your meters readout at that voltage range?
 
  #17  
Old 06-10-2011, 11:29 AM
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[QUOTE=timbersteel;10443065]I would do a resistance check from the PCM harness to the TPS connector. how do i check this?

yes i had the battery disconnected over night.

i just back probed the connector while the tps was hooked up should i unhook it and re-test it?

not shure on the idle screw.

one minute it will idle fine with no cel and the next it wont idle and the cel is on and while driving down the road it seems like the throttle is dead with the pedel depressed 1% to 20% down and then it will jump and go good till i let off the throtle. so i think it is something to do with the tps. and the only code i get out of the ordinary is 122, i get tranny codes but that is because the po put a 5-speed in a automatic truck. any help is greatley aperciated
 
  #18  
Old 06-10-2011, 12:06 PM
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You stated: .09-4.21v with a steady increase to wot and decrease to closed position.

That is not in specification. The closed throttle TPS value should not fall below 0.6 VDC. That is the reason for the 122 Code.
 
  #19  
Old 06-10-2011, 12:47 PM
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Originally Posted by rla2005
You stated: .09-4.21v with a steady increase to wot and decrease to closed position.

That is not in specification. The closed throttle TPS value should not fall below 0.6 VDC. That is the reason for the 122 Code.
Yep you're right good catch, I see missed that 0 in there. I had read it as .9v rather then .09v

An adjustment of the TPS should/might be enough to correct for it.
 
  #20  
Old 06-10-2011, 02:49 PM
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how do i adjust it correctly?
 
  #21  
Old 06-10-2011, 05:23 PM
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Most of the TPS sensors for these trucks I have seen have very little to no adjustment. I wonder if a previous owner has jacked with the Idle Stop Screw? If you disconnect the IAC does the truck die? It should drop the idle down to the 400-550 RPM range IIRC. Moving that screw will negatively affect the TPS output voltage.
 
  #22  
Old 06-10-2011, 06:10 PM
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i didnt try to un plug it i will do that in the morning. what would the corrective action be to fix it if it does die?
 
  #23  
Old 06-10-2011, 07:02 PM
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Most of the TPS sensors for these trucks I have seen have very little to no adjustment.

Yea me either, only the little slop in the screws would allow for. No actual adjustment "slots" built in allowing one to be rotated couple degrees.

how do i adjust it correctly?

I posted it up in #16 you must have missed it. Book states,

To adjust (91 and up) loosen tps screws, connect negative probe to the terminal with the gray/red wire and the positive probe to the terminal with the grey/white wire. rotate sensor with the ignition key "on" until the output reads 1.0 volt. Tighten screws recheck voltage.


You might get enough to make the difference even though as with rla2005 and I never seen any amount of intended / built in adjustment in the TPS, least not for the model year.

If the throttle plates are not digging into the throttle body when fully closed you might better elongate the mounting holes in the tps a tad if needed, rather then mess with that stop screw. Simply drilling the tps mount holes out couple sizes larger would add in some degree of adjustment to it.
 
  #24  
Old 06-10-2011, 07:32 PM
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there was enough light out yet to do a little more work to my truck so here is what i found.

i let the truck warm up and pulled the iac wires off and there was no change in idle.

i have a 351 and would have to pull the throttle body off to do that. is it possible to adjust the tps with the throttle body off the truck.
 
  #25  
Old 06-10-2011, 08:52 PM
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I believe you can. Personally I would remove it, I will go just a little farther so i dont struggle for three hours on something that could take 5 minutes. "enough [effing] around" as i always say...

So you need a new IAC then?
Would IAC change how the engine runs beyond Idle?
 
  #26  
Old 06-11-2011, 09:29 AM
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SO I double checked my readings and it should be .9v not .09v so that sounds correct.

if my iac was bad why would i have a dead throttle part way down and a code 122?

what else should i look for? any ideas?
 
  #27  
Old 06-11-2011, 06:52 PM
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Originally Posted by 2005f-150
SO I double checked my readings and it should be .9v not .09v so that sounds correct.

if my iac was bad why would i have a dead throttle part way down and a code 122?

what else should i look for? any ideas?
I am a little confused here with the statement in bold above. Is the TPS output .9 or .09 VDC with the throttle closed?
 
  #28  
Old 06-11-2011, 07:35 PM
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the correct reading is .9v i acidently put a 0 in front of it. i wrote it down on a piece of paper correctly, just typed it wrong. but i double checked my readings
black wire-1.4ohms
orange wire-5.05v
green wire-.9-4.21v

sorry for the confusion
 
  #29  
Old 06-11-2011, 07:52 PM
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Originally Posted by 2005f-150
there was enough light out yet to do a little more work to my truck so here is what i found.

i let the truck warm up and pulled the iac wires off and there was no change in idle.

i have a 351 and would have to pull the throttle body off to do that. is it possible to adjust the tps with the throttle body off the truck.
Something is wrong in the IAC, the idle should have dropped when the harness connector was removed.

Whats the idle speed?

Any yes you can test/adjust the TPS with the throttle body removed, wouldn't effect reading/setting. And yea no real way to do it with it in place!

Originally Posted by 2005f-150
the correct reading is .9v i acidently put a 0 in front of it. i wrote it down on a piece of paper correctly, just typed it wrong. but i double checked my readings
black wire-1.4ohms
orange wire-5.05v
green wire-.9-4.21v

sorry for the confusion
.9v throttle closed is fine, perfect in fact.

black wire-1.4ohms

You continue to post that value but its pretty much meaningless without knowing what the black wire connects to and how your taking that reading.

To test the TPS resistance you must remove the harness connector and test the TPS itself, not done by back probing at the connector.

Are you using a analog or digital meter? analog is the best choice for testing TPS. Digital meter will likely not react quickly enough and or smooth over any "blips", masking any bad spots it may have you'd want to see during the testing.
 
  #30  
Old 06-11-2011, 08:44 PM
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i have a digital meter.
i tried to look at at tonight and i broke one of the plastic clips that holds the connector on, but i got around 8.6ohms doesnt sound right so i will double check it in the morning to be shure.
 


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