TPS sensor HELP ME!

Information on the naturally-aspirated KA24E and KA24DE engines.
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240_fun
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Car: 92 Nissan 240sx Hatch, 2000 Ford Ranger XLT

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I just did the ohm test on the tps sesorthe resistance is supposed to go from 2-10 when you open the throttle, but mine goes from 10 to -2 when opening. did i do something wrong or is it a bad sensor?
Modified by 240_fun at 3:23 PM 12/3/2007


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krazydriver
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Car: 2002 civic ex, 1993 KA-T 240sx - parting it out...

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I always check with the ignition on.

One wire should be a constant +5 volts with the key on, black wire is ground and the other is signal. The the signal should fluctuate between ~0v and 5v while moving the throttle.

FSM says this:Fully closed throttle: 2 ohmspartial throttle : 2-10Fully open: 10ohms

You also need to verify that fully closed the sensor output voltage is between .2 ~ .5 volts. This ensures the ECU is reading it properly.

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240_fun
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Car: 92 Nissan 240sx Hatch, 2000 Ford Ranger XLT

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output voltage its between the #2 and #3 wires? ~.45-.55resistance is between #1 nd #2..... 2-10 as you open the trottle plate?nd power supply is between #3 and ground right? ~5vdid i get that all right?with the ign on?

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krazydriver
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power supply is measured between #1(pwr) and #3(ground), should be steady 5v with the key on.

just keep in mind Ignition OFF if your measuring the resistance(partly because you'd have to unplug the sensor harness), like i said i just measure the voltage with the key on, same information just a different way of testing.

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240_fun
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Car: 92 Nissan 240sx Hatch, 2000 Ford Ranger XLT

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got around to doing the test output was .42power supply was a constant 5.12 open or closed nd resistance was 11.08 constant open or closedboo bad tps

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shpaintball
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Car: 90' SOHC 240sx RIP, 92 DOHC KA project STOLEN 87 FC RX-7 TURBO ...93 KA died...89 SR20 DD..08 Titan new toy

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i think you may have the current running backwards some how...just a quick thought....didnt really look much into it..

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240_fun
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Joined: Sat Sep 01, 2007 2:43 pm
Car: 92 Nissan 240sx Hatch, 2000 Ford Ranger XLT

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I got a new one anywayWasnt too expensive...comes in tuesdayso install maybe that afternoon

Moto Man
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Joined: Fri Oct 15, 2004 8:16 pm
Car: 93 240SX

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lol, the service manual has it backwards. Your TPS is fine.

DjPantsSpecR
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Joined: Fri Jan 14, 2005 12:49 pm
Car: 93 Nissan MS13
92 Nissan RMS13

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FALSE

the manual isnt wrong. you just measured between the wrong terminals.

if you read between two terminals it goes from 10 to 2, and if you read between two other terminals it reads from 2 to 10

classic TPS mistake

either way krazydriver is right, you should check the voltage to see if everything is okay. checking resistance is really only useful for setting the TPS position

guyaverage
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Joined: Thu Feb 19, 2004 9:48 am
Car: Nissan 240SX Convertible

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DjPantsSpecR wrote:FALSE

the manual isnt wrong. you just measured between the wrong terminals.
FALSE

If you compare the two terminals shown in the manual, then do the measurements exactly as shown in the picture, the manual has it BACKWARDS.

DjPantsSpecR
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Joined: Fri Jan 14, 2005 12:49 pm
Car: 93 Nissan MS13
92 Nissan RMS13

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dont you shake your finger at me!

no you're right i remember now, its been so long since ive had to peak in my FSM. But i do distinctly remember InsanityInc running into this same problem only to figure out that if you switch the terminals the resistance changes as ive indicated.

it certainly isnt the first place the manual is wrong though either....

guyaverage
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Joined: Thu Feb 19, 2004 9:48 am
Car: Nissan 240SX Convertible

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DjPantsSpecR wrote:
it certainly isnt the first place the manual is wrong though either....
You arent kidding, there are errors all over it! If I'm reading the cam specs right, it looks like they are showing the duration as 248/240 (int/exh) instead of what we all know as 240/248.

Who knows, I never know when to trust it and when not to.

We should start a list of known errors and make it a sticky.

DjPantsSpecR
Posts: 1711
Joined: Fri Jan 14, 2005 12:49 pm
Car: 93 Nissan MS13
92 Nissan RMS13

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thats a good idea actually

and the cam thing is the first item that comes to mind as an error, and what you say is right, it is backwards


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