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TPS reading 4 volts??

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Old Jun 14, 2014 | 03:41 PM
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TPS reading 4 volts??

Recently changed out the emissions harness and tps on my 87 n/a. I go to adjust the TPS and its reading two volts and its not changing when I adjust the screw. Does anyone know whats going on?
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Old Jun 14, 2014 | 03:41 PM
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From: Ewing, NJ
It was reading 4 volts then it fell to 2.14 randomly.
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Old Jun 15, 2014 | 10:56 AM
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Which wire color and was the engine as hot as it possibly could get?
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Old Jun 15, 2014 | 11:07 AM
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I was on the green/red and i think so but not sure, my temp sensor is broken.
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Old Jun 15, 2014 | 12:04 PM
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What does the temp sensor have to do with it. Getting back to the TPS, it needs to be measured as stated above. And if you press down on the screwdriver when setting it the voltage will increase.
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Old Jun 15, 2014 | 12:49 PM
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I just replaced a TPS in one of my cars that was reading 4 volts at idle and wouldn't change much after adj. Swapped it and adj to the normal .70 or so. This was for an FD.

I think your sensor is bad.
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Old Jun 15, 2014 | 01:32 PM
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Originally Posted by satch
What does the temp sensor have to do with it. Getting back to the TPS, it needs to be measured as stated above. And if you press down on the screwdriver when setting it the voltage will increase.
Temp gauge my bad, i mean im not sure if the motor was warmed up all the way.
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Old Jun 18, 2014 | 11:53 AM
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Got a new temp gauge and warmed engine all the way up. Its reading around 4.13 volts. Is it safe to say i need a new tps?
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Old Jun 18, 2014 | 12:04 PM
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Originally Posted by RobbyP33
Got a new temp gauge and warmed engine all the way up. Its reading around 4.13 volts. Is it safe to say i need a new tps?
You need to drive the car for about 20 mins than adjust it
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Old Jun 18, 2014 | 12:35 PM
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From: Ewing, NJ
I did that it still reads 4.13 volts
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Old Jun 18, 2014 | 01:52 PM
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From: tulsa,ok.
If it reads over 4 volts w/the engine idling at an acceptable rpm then chances are you need to replace the sensor. The other two wires should read 0 volts (ground wire) and the Vref would read 5 volts, both tested w/the key to on. W/the engine off,key to on and engine fully warmed the sensor should read close to 4.5 volts fully extended and about 1 volt when the piston of the TPS is receded almost all the way (but not completely receded/hidden within the sensor). And finally make sure the sensor plug is snugly connected to the emission harness.
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Old Jun 18, 2014 | 04:22 PM
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What do you mean when you stay the plug is hiddin within the sensor?
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Old Jun 18, 2014 | 05:12 PM
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From: tulsa,ok.
Originally Posted by RobbyP33
What do you mean when you stay the plug is hiddin within the sensor?

I didn't. I stated something about the piston/plunger being recessed within the TPS.
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Old Jun 18, 2014 | 06:01 PM
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From: Ewing, NJ
Originally Posted by satch
I didn't. I stated something about the piston/plunger being recessed within the TPS.
Where is the piston?
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Old Jun 18, 2014 | 06:44 PM
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From: tulsa,ok.
You know that round column looking thing which comes out of the TPS. I mean there are only so many parts to the TPS and only one part which moves.
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Old Jun 19, 2014 | 07:43 AM
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Originally Posted by satch
You know that round column looking thing which comes out of the TPS. I mean there are only so many parts to the TPS and only one part which moves.
Yes I know what youre talking about. That part moved before I even put it on the car. Is that supposed to happen?
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Old Jun 19, 2014 | 10:29 AM
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Originally Posted by RobbyP33
Yes I know what youre talking about. That part moved before I even put it on the car. Is that supposed to happen?
Is what supposed to happen?
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Old Jun 19, 2014 | 10:42 AM
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Is the part supposed to be loose and turn, because i dont think my previous TPS did that
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Old Jun 19, 2014 | 10:56 AM
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Originally Posted by RobbyP33
Is the part supposed to be loose and turn, because i dont think my previous TPS did that
It's supposed to extend and recede as in doing that it sends a signal to the ECU. If you wanted to you can rotate it but that changes nothing w/respect to the signal it outputs and it doesn't rotate when in use.
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Old Jun 20, 2014 | 01:59 PM
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From: Ewing, NJ
Originally Posted by satch
It's supposed to extend and recede as in doing that it sends a signal to the ECU. If you wanted to you can rotate it but that changes nothing w/respect to the signal it outputs and it doesn't rotate when in use.
I checked it today while I was putting in an AC belt and it does extend and recede. I do have a working TPS (was the old one) but it dosent have the 3 prong connector to match the harness, do you know where i can find just the connector?
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Old Jun 20, 2014 | 04:30 PM
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From: tulsa,ok.
Use the one off the TPS which is in need of replacement.
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Old Jun 20, 2014 | 04:59 PM
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Originally Posted by satch
Use the one off the TPS which is in need of replacement.
I dont want to do that because then i can return the broken TPS
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Old Jun 20, 2014 | 05:32 PM
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From: tulsa,ok.
Then you'll have to pull one off a junk yard car if you could find one or purchase a used one on the cheap and remove its plug.
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