Throttle Position Sensor setting???

attackdog

New member
I picked up a code 22 so I replaced the TPS and the "check engine" light has now turned off. I was told that the TPS needs to be adjusted to the correct voltage setting but I did a search and couldn't find anything on how to set it? Can someone give me some info on how to adjust the TPS and how to set it to the proper voltages? Thanks.
-Dean
 

MRKING

New Parts for Old Trucks
Re: Throttle Position Sensor setting???

set screw on the throttle body blades when adjusted is also attached to the tps sensor on the other end of the linkage . have you moved the screw in or out lately ?
 

JSM

Active member
Re: Throttle Position Sensor setting???

Chances are it doesn't need adjust at all. Truck run fine now? Does it idle like it should?
 

Don W.

Stab it and steer it
Re: Throttle Position Sensor setting???

:2cents:Other than the small amount of play in the screws there is no adjustment. Use Datamaster to check that the ECM is showing full throttle. Visually check that you're getting FT. Throttle plates are closed at idle. IAC controls idle speed. If adjustment screw seal is gone you should check that.:2cents:
 

NJ93TY

Donating Member
Re: Throttle Position Sensor setting???

You should have about .5V at closed throttle and 4.5-5V at WOT I believe
 

attackdog

New member
Re: Throttle Position Sensor setting???

Thanks all. The truck seems to be running good. So I am afraid to touch it. I will look it over with the advice given, but I think it is fine. Thanks again.
-Dean
 

MRKING

New Parts for Old Trucks
Re: Throttle Position Sensor setting???

id still check your tps voltage output . if its off , your ecm sees different that what really is while driving . could have adverse effects on optimal performance .
 

ViciousV6

400HP/550FTLB
Re: Throttle Position Sensor setting???

yes you should make sure your at .5 volts at idle don't wanna be at .0, and always check with motor off and key on if you getting WOT throttle.
 

attackdog

New member
Re: Throttle Position Sensor setting???

O.K. There are the 3 wires, so with a voltmeter, what wires do I check and what do they do? Thanks again.
-Dean
 

NJ93TY

Donating Member
Re: Throttle Position Sensor setting???

BLK is ground, DK Blue is TPS signal, ( this will change depending on your throttle position) GRY is 5V reference. Take a voltmeter, negative to black wire, other end of meter to GRY, make sure you have 5V reference. Then move the meter to the DK blue wire, at closed throttle you should be around .5 V, slowly open the throttle and the voltage should slowly climb towards 4.5-5V.
 

i8av8

Donating Member
Re: Throttle Position Sensor setting???

BLK is ground, DK Blue is TPS signal, ( this will change depending on your throttle position) GRY is 5V reference. Take a voltmeter, negative to black wire, other end of meter to GRY, make sure you have 5V reference. Then move the meter to the DK blue wire, at closed throttle you should be around .5 V, slowly open the throttle and the voltage should slowly climb towards 4.5-5V.


first time i got .49v at closed. second time i got .48v at closed.
first time i got 4.2v at wot. second time i got 4.1v at wot.

could this be a tps going bad or already bad or do i need to adjust the throttle blade screw?

sorry, but i didn't want to start a whole new thread.
 
Re: Throttle Position Sensor setting???

There is no "set up " for the TPS. The ecm samples the voltage drop at the sensor just before start up and calls that voltage "0". Then anything 4 volts or so above that initial reading equals WOT. So, as long as the initial voltage at the TPS is less than 1 volt the ecm will be happy (going from memory so the actual numbers may be slightly off). I had a prob with my old TPS giving weird readings at closed throttle, so instead of buying a new one I adjusted it. Worked for a while, ended up just replacing it.

and

The TPS isnt self adjusting, the ECM just auto zero's the throttle percent value when the key is turned on. So, if your TPS is dropping .7volts at startup, the ecm sets that value as 0 percent throttle. Then it raises the throttle percent up to 100 percent when the TPS reads about 3.8 volts higher than its initial reading at startup. Making sure 100 percent TPS corresponds with the butterflies being wide open is one key issue.

As long as your ECM sees less than about 1 volt from the TPS at startup it will not toss a code.
Adjusting the TPS really doesnt do a thing in our application, performance wise.



There ya go.
 
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