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Discussion Starter · #1 · (Edited)
I've been asked for this several times so I decided to do a write up on how I have done mine.

The Nissan TPS uses two 3 wire connectors on it. One is on a short section of harness about 6 inches long and handles the actual throttle position signal and the other made to the body of the sensor is for the idle validation circuit which you also need or you get a code (51 I believe). With the sensor standing up, with the mounting tabs on the right side and the TPS wiring harness coming out of the bottom while your looking at it the top 2 pins in the connector made in the sensor body are your idle validation pins so disregard the bottom pin. Your TPS wiring harness that comes from the bottom of the sensor will terminate at a 3 prong plug and have red, white, and black wires in it. The wires colors correspond with these functions:

Red is the 5 volt input wire

White is the TPS signal wire

Black is the sensor return wire

With the connector lock up the white wire will be in the center, the red wire should be on the left, and the black wire should be on the right. My car is an 88 so I can give wire colors for an 88 Toyota Supra.

Brown is the E2 wire for the sensor return

Blue with a red stripe is the Vc wire for a 5 volt supply

Yellow with a blue stripe is your IDL wire for Idle validation

White with a red stripe is your VTA or throttle position signal

You take your brown E2 wire and branch it into 2 seperate leads. One will go to the idle validation switch and one will go to the TPS harness connector. You can put the one E2 wire(brown) on either the top or second post of the idle validation connector( the one made on the sensor body itself) and the IDL ( yellow with the blue stripe) will go to the other. Then the other E2 wire(brown) will go to the black wire in the Nissan TPS harness, VTA wire(white with red stripe) will go to the white wire in the Nissan TPS harness connector, and the Vc wire(blue with red stripe) with go to the red wire in the Nissan TPS harness connector.

When adjusting this sensor I found the best TPS voltage was around .385 on the sensor check of my S-AFC. This will trigger the idle validation at 3 to 4% throttle which takes alittle getting used to at the pits at the track or light cruise loads but it turned out the code and gets a 100% throttle reading on the afc. I hope this helps any questions I can answer feel free to ask.

Sean
CWF Dyno Services
 

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Nice writeup!

Can you take any pics of the throttlebody and your wiring to see how you installed it or perhaps make a small scetch on MS-paint to make it a bit more clear how to do the wiring.

Anybody know if the wire colors are the same in 89-92 Supras?

How big is the stock TB compared to the Q45?

Found some pics of the Q45 TB:

 

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Discussion Starter · #4 ·
Stock is roughly 65 mm and the Q45 is roughly 83 or 84 mm. I used parts of the Nissan harness which I have found can be different colors for different years and different cars that's why I did not take pictures but I will draw out a diagram and post it.

Sean
 

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why would having this monster throttle body help if you still only have 2.5-3 inch intercooler piping?? please explain, looks like a good mod if it can help flow alot more for only an hour of my time or less.
 

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Beats and Rhythm
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YOU ARE THE MAN!

Thank you so much!

-Jonathan
 

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selz202 said:
I always thought the Q45 was 90mm... :scratch: am i looking at newer ones i take it?

They are all the same, 90mm is the outside dimension.
 

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Sean, I just wired my Q45 up today, looking at the pic, I think I put my IDL on the wrong pin, or does it matter?

The question I had for you is, does it matter how the box is screwed back in? I hope this makes sense... When I mounted the box back onto the side of the TB, you can move it up and down, or twist it really... Does it have to be set to a certain position? I tried to just use the indentions from the screws and put it back like it was...

Is there anything else I need to do? Im using the AEM, do I need to tell it that Im using a Q45, or just tell it Im using the stock TB? AGH! This is getting confusing...
 

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Life is BOOST
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Sean, I just wired my Q45 up today, looking at the pic, I think I put my IDL on the wrong pin, or does it matter?

The question I had for you is, does it matter how the box is screwed back in? I hope this makes sense... When I mounted the box back onto the side of the TB, you can move it up and down, or twist it really... Does it have to be set to a certain position? I tried to just use the indentions from the screws and put it back like it was...

Is there anything else I need to do? Im using the AEM, do I need to tell it that Im using a Q45, or just tell it Im using the stock TB? AGH! This is getting confusing...
The twisting in the box is how you would adjust the TPS signal/voltage to the ecu. You would use lets say an SAFC if you had one, go to sensor mode, and you would see the voltage change as you twist the black box. Now the Stock ECU likes to see a certain voltage range to avoid throwing codes/engine light. But with the AEM, like you said, you pretty much install the Q45 TB, connect it, then tell the AEM what the voltage range is from Idle (meaning the pedal is NOT pressed) to full throttle (pedal floored) I'm not sure if the AEM's wizard has the Q45 TB as an option. Someone correct me if I'm wrong. Hope that helps
 

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Thanks turbogate... Im assuming it has something in there for the Q45, I know Im not going to be the fiorst guy ever to use the AEM on a 7M with a Q45... Its like the closer I get to finishing this thing, the more complicated its becoming... :)
 
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