TPS worries...voltage and resistor, WOT V ?
10-09-2012, 06:51 AM
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TPS worries...voltage and resistor, WOT V ?
Hi, i am looking for specific info for the TPS on my 22REC 1986.
I have many manuals about this truck and all of them gives resistor tables to "check" the tps...
So the other day i was doing maintenance on my truck and thought it would be correct to check the TPS since its been there since 1986 untouched.
I am used to measure voltage for tps with a scope to see if its regular.
At WOT i measure 3.9V
wtf ?
i had a new in box TPS ($$$) that i replaced it with, set it up to factory spec with feeler guages, same thing, or very close.
Throtle plate opens fully.
I then measured computer input impedance to check the cause of this low unexpected WOT voltage...nothing there wrong.
So, would it be possible at all that the 22REC "antique" ecu/efi system detect WOT at 3.9v ??
doesnt sound right to me...even in the shilton manual, they refers to the tps as a 0-5v readout unit to the ecu...
the truck runs "ok" and i never had issues realy with that, i am just wondering...
thanks for any details on that.
I have many manuals about this truck and all of them gives resistor tables to "check" the tps...
So the other day i was doing maintenance on my truck and thought it would be correct to check the TPS since its been there since 1986 untouched.
I am used to measure voltage for tps with a scope to see if its regular.
At WOT i measure 3.9V
wtf ?
i had a new in box TPS ($$$) that i replaced it with, set it up to factory spec with feeler guages, same thing, or very close.
Throtle plate opens fully.
I then measured computer input impedance to check the cause of this low unexpected WOT voltage...nothing there wrong.
So, would it be possible at all that the 22REC "antique" ecu/efi system detect WOT at 3.9v ??
doesnt sound right to me...even in the shilton manual, they refers to the tps as a 0-5v readout unit to the ecu...
the truck runs "ok" and i never had issues realy with that, i am just wondering...
thanks for any details on that.
10-09-2012, 08:13 AM
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How do you know what the input impedance "should" be? (and for that matter, how did you measure it -- you can't measure input impedance with just an ohmmeter).
According to the manual http://www.ncttora.com/fsm/1990-1995...e/troubles.pdf the TPS WOT voltage should be 3.2-4.9 volts. Why do you think 3.9 is out of spec? Did you replace the TPS based on the WOT voltage?
According to the manual http://www.ncttora.com/fsm/1990-1995...e/troubles.pdf the TPS WOT voltage should be 3.2-4.9 volts. Why do you think 3.9 is out of spec? Did you replace the TPS based on the WOT voltage?
10-09-2012, 08:25 AM
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How do you know what the input impedance "should" be? (and for that matter, how did you measure it -- you can't measure input impedance with just an ohmmeter).
According to the manual http://www.ncttora.com/fsm/1990-1995...e/troubles.pdf the TPS WOT voltage should be 3.2-4.9 volts. Why do you think 3.9 is out of spec? Did you replace the TPS based on the WOT voltage?
According to the manual http://www.ncttora.com/fsm/1990-1995...e/troubles.pdf the TPS WOT voltage should be 3.2-4.9 volts. Why do you think 3.9 is out of spec? Did you replace the TPS based on the WOT voltage?
its 1.2mohm by the way.
high enough to not bother the tps.
i dont know what it should be, other than since its an input, it MUST be high impedance.
yes you can measure impedance of such circuit with "just" an ohm meter, because of the simple nature of the circuit.
not knowing the WOT value of the VOLTAGE, i assumed it would be as close as possible to 5v. i never ever said it was out of spec. you get me wrong right from the start.
Last edited by patallen; 10-09-2012 at 08:27 AM.
10-09-2012, 10:02 AM
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Good luck!
10-09-2012, 10:43 AM
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why do you act like a douche bag with me ??
it was not simple enought to just say what was the correct wot voltage ? that would have straightened the facts right from the start, and its was all i needed.
Conclusion, my TPS is just ok.
you talk to me like if i where a complete idiot. i am electronic engineer for the automotive market, RF designer and software programmer.
25 years of experiences
3 us pattens
2 cnd pattens
all related to electronic devices meant for cars.
If you have a hand held remote for ANY of you cars, i am probably responsible of its design, partialy or totaly.
will you start quoting every single sentence i write, just because you think you are smarter ??
by the way, thoses analogue dash guages REQUIRES a resistor pull-up value to show proper range, because they rely on a single variable resistor...you quote that as if it where an absolute verity and the only thing to rely on...you make yourself asumptions based on a complete lack of intelligence.
ANY voltages read out at the ECU are high impedance internally, except some cases where there is a pull-up resistance needed, such as the temp sensor since its only one resistor alone, not a potentiometer with its own voltage source/reference.
MORRON !!!
it was not simple enought to just say what was the correct wot voltage ? that would have straightened the facts right from the start, and its was all i needed.
Conclusion, my TPS is just ok.
you talk to me like if i where a complete idiot. i am electronic engineer for the automotive market, RF designer and software programmer.
25 years of experiences
3 us pattens
2 cnd pattens
all related to electronic devices meant for cars.
If you have a hand held remote for ANY of you cars, i am probably responsible of its design, partialy or totaly.
will you start quoting every single sentence i write, just because you think you are smarter ??
by the way, thoses analogue dash guages REQUIRES a resistor pull-up value to show proper range, because they rely on a single variable resistor...you quote that as if it where an absolute verity and the only thing to rely on...you make yourself asumptions based on a complete lack of intelligence.
ANY voltages read out at the ECU are high impedance internally, except some cases where there is a pull-up resistance needed, such as the temp sensor since its only one resistor alone, not a potentiometer with its own voltage source/reference.
MORRON !!!
10-09-2012, 02:33 PM
#7
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why do you act like a douche bag with me ??
it was not simple enought to just say what was the correct wot voltage ? that would have straightened the facts right from the start, and its was all i needed.
Conclusion, my TPS is just ok.
you talk to me like if i where a complete idiot. i am electronic engineer for the automotive market, RF designer and software programmer.
25 years of experiences
3 us pattens
2 cnd pattens
all related to electronic devices meant for cars.
If you have a hand held remote for ANY of you cars, i am probably responsible of its design, partialy or totaly.
will you start quoting every single sentence i write, just because you think you are smarter ??
by the way, thoses analogue dash guages REQUIRES a resistor pull-up value to show proper range, because they rely on a single variable resistor...you quote that as if it where an absolute verity and the only thing to rely on...you make yourself asumptions based on a complete lack of intelligence.
ANY voltages read out at the ECU are high impedance internally, except some cases where there is a pull-up resistance needed, such as the temp sensor since its only one resistor alone, not a potentiometer with its own voltage source/reference.
MORRON !!!
it was not simple enought to just say what was the correct wot voltage ? that would have straightened the facts right from the start, and its was all i needed.
Conclusion, my TPS is just ok.
you talk to me like if i where a complete idiot. i am electronic engineer for the automotive market, RF designer and software programmer.
25 years of experiences
3 us pattens
2 cnd pattens
all related to electronic devices meant for cars.
If you have a hand held remote for ANY of you cars, i am probably responsible of its design, partialy or totaly.
will you start quoting every single sentence i write, just because you think you are smarter ??
by the way, thoses analogue dash guages REQUIRES a resistor pull-up value to show proper range, because they rely on a single variable resistor...you quote that as if it where an absolute verity and the only thing to rely on...you make yourself asumptions based on a complete lack of intelligence.
ANY voltages read out at the ECU are high impedance internally, except some cases where there is a pull-up resistance needed, such as the temp sensor since its only one resistor alone, not a potentiometer with its own voltage source/reference.
MORRON !!!
Just a casual observation...
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