did i set tps correct?

[Alex Bland]

i just got my tb all put together now before i put it on the car i want to make sure i set it right. between pins 1 and 2 its 4980 ohms, between 1 and 4 its 4770 ohms

 

[giovanniv]

I thought pins 1 and 4 were supposed to be .9 ohms and when you opened up the throttle body and used pins 1 and 3 it was supposed to b 5k ohms?

 

[steve]

Guys, the VFAQ is wrong. A little searching here would explain why.

1G TPS gets adjusted to output between 0.48v and 0.52v unless your running DSMLink.
2G TPS gets adjusted by setting the internal IPS switching point.

 

[Alex Bland]

is the output 1&4?

 

[steve]

No, 1 and 4 are the two ends of the resistor that makes up the TPS. Measuring the resistance between them should be 3.5k to 6.5k ohms according to the spec.

Pin 2 is the wiper (the part that moves across the resistor) which is the output to the ECU. The resistance between 2 and 4 or 2 and 1 should change smoothly as you turn the tangs that couple with the throttle shaft.

If you have a SAFC or logger you can measure the TPS voltage with the ignition on. Otherwise you have to probe the pins of the TPS or ECU to measure the output voltage.

 

[Alex Bland]

No, 1 and 4 are the two ends of the resistor that makes up the TPS. Measuring the resistance between them should be 3.5k to 6.5k ohms according to the spec.

Pin 2 is the wiper (the part that moves across the resistor) which is the output to the ECU. The resistance between 2 and 4 or 2 and 1 should change smoothly as you turn the tangs that couple with the throttle shaft.

If you have a SAFC or logger you can measure the TPS voltage with the ignition on. Otherwise you have to probe the pins of the TPS or ECU to measure the output voltage.

alright sorry steve im making this more complicated then it needs to be, so the 2 and 4 or 2 and 1 that changed smoothly.. thats the one rated to be 0.48v and 0.52v correct? or is it ohms?

 

[steve]

Sorry, it's been a long time since I learned how a Potentiometer worked so I'm not making it easy for you to understand.

In the car pin 1 is connected to the 5v sensor power and pin 4 to ground. Pin 2 is the output and depending on where it touches the surface of the resistor connected between 1 and 4 it gets a voltage that varies in proportion to it's position.

That resistor between 1 and 4 is nominally 5k ohms but anything between 3.5k and 6.5k ohms is acceptable. That resistance is fixed. The +5v sensor power is nominally 5 volts but can vary between cars and to a much smaller amount as the battery voltage changes. These tolerances are why you can't just pull some resistance value off a web page and blindly use it to set the TPS. They effect the output voltage you'll get at pin 2 by changing the voltage applied across the resistor and the amount of resistance in the legs of the voltage divider the Potentiometer creates and determines the output voltage

 

[giovanniv]

Ahh crap! I went off vfaq and I set mine to .9 ohms and now it wants to idle at 2k rpms . That explains it!!!

 

[steve]

Once the IPS tells the ECU that the throttle is closed it will start trying to lower the idle speed but if the idle doesn't come down by adjusting the BISS then you have additional issues.

 

[giovanniv]

The idle does come down with moving the biss screw but I can turn the biss screw in pretty far in and the closest I get is like 1500rpms. I have my tps set at like .915ohms.

Oh and I have a 1g 7 bolt . That is why I am all messed up!

 

[Alex Bland]

oh so basicly your saying all you can do is set pins 1 and 4 inbetween 3.5k and 6.5k ohms then thats all you can really do to "set" the tps..now i dont have a logger or anything so how could i set the volts on the other?

 

[steve]

oh so basicly your saying all you can do is set pins 1 and 4 inbetween 3.5k and 6.5k ohms then thats all you can really do to "set" the tps..now i dont have a logger or anything so how could i set the volts on the other?

No what I'm saying is for a TPS to be good it has to measure at least 3.5k ohms between 1 and 4 and no more than 6.5k ohms. You can't do anything about that besides measure it.

It also has to while measuring between 2 and 4 change resistance smoothly as you rotate the center shaft.

Those are validation tests to see if you have a good part.

The adjustment requires you to hook the TPS to the throttle body, attach the connector, turn on the ECU and then measure the voltage at pin 2 either by probing the wire at the TPS, probing pin 19 at the ECU, using a datalogger, or the sensor voltage check on a SAFC since it is also connected to the TPS signal, then turning the TPS body until you read about 0.5v as the output voltage.

The idle does come down with moving the biss screw but I can turn the biss screw in pretty far in and the closest I get is like 1500rpms. I have my tps set at like .915ohms.

Oh and I have a 1g 7 bolt . That is why I am all messed up!

I'm assuming your still talking about a 2G car, if not you need to clarify.
It doesn't matter if you had a 1G 6 bolt in there since you should be using the 2G TPS since it has the internal IPS that the wiring harness is set up for.

 

[BIRDCLAWTSi]

He is saying the voltage should be between 0.48v and 0.52v on pins 2 and 4 or 1 and 2 of the tps. To find out which 2 it is , Connect the voltmeter and move the throttle and watch the meter. Should be a smooth transition from closed to full throttle.

 

[steve]

The TPS output voltage should be measured between pin 2 and sensor ground which happens to be pin 4 on the TPS.

 

[Alex Bland]

alright i understand now sorry im not to bright with these kinda things..mmk thanks alot! ill do that

 

[Bojangles465]

I've always heard .63v, which one is it, .63 or .48 to .52?

 

[jrdrew5]

Some one do a start to finish of the process to replace the other one . One for ecmlink and one not.

 

[steve]

I've always heard .63v, which one is it, .63 or .48 to .52?

Depends.

The Factory says to adjust a 1G TPS to output 0.48v to 0.52v with the throttle closed.

ECMTuning says to use 0.63v with DSMLink.

 

[spadepro22]

ECMTuning says to use .63v with DSMLink.

Do you know whats reason for this?

 

[Clew]

Be sure and move it while you got the meter on it to check the potentiometers variable resistor property's, power on or off, Vdc or ohms... Hoped that helped