Ques about tps volt vs tps %
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From: J-ville,NC
Ques about tps volt vs tps %
Here's the thing. At idle, the tps voltage is .69 vdc but it shows 13% throttle according to datamaster. If I turn the car off and restart it everything is fine. Is there a calibration that needs to be done? THanks
Last edited by wicked_95z; Jul 27, 2007 at 10:14 PM.
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From: Saginaw, Michigan
http://shbox.com/1/4th_gen_tech2.html#iac_reset
That might help. Not sure if it is your problem though.
Dan
That might help. Not sure if it is your problem though.
Dan
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From: Houston(clear lake)
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From: Saginaw, Michigan
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From: Saginaw, Michigan
Is something keeping your throttle blades from closing, like the throttle blade screw? At 13% throttle, I'm at 1.02V. At closed throttle, I'm at 0.59. Do you know your IAC counts at idle?
What is your idle speed?
Dan
What is your idle speed?
Dan
Last edited by stereomandan; Jul 10, 2007 at 07:49 PM.
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From: J-ville,NC
My IAC counts are right around 60. When I start it up and the TPS says 13% and .69 vdc, it idles about 12-1300. When I shut it down and restart it making no changes, everything is normal. 0% TPS and .69 vdc and the idle is 850-900
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Check your TP sensor with an ohm meter from closed throttle to WOT, make sure the sensor its self is good. make sure the sensor is properly engaging the throttle blade shaft. Did you have this problem before you slotted it? or did it start as a result of slotting it?
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From: Hell was full so they sent me to NJ
The TPS reference circuit is 5.0V. The reference voltage does not limit how low the closed throttle voltage can go. That's the result of the amount of resistance in the circuit with the sensor in the "closed" position.
Does sound like the sensor may not be indexed to the blade properly. Might be worth checking, then clearing the PCM and trying again. Anything above 0.20V and below 0.90V at closed throttle startup should be recognized by the PCM as 0% TPP.
Does sound like the sensor may not be indexed to the blade properly. Might be worth checking, then clearing the PCM and trying again. Anything above 0.20V and below 0.90V at closed throttle startup should be recognized by the PCM as 0% TPP.
Last edited by Injuneer; Jul 11, 2007 at 05:20 PM.
brain fart my bad.
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From: J-ville,NC
Well after fixing some other issues I was able to dig into the TPS but came up with nothing. I pulled the TPS and reinstalled it. Reset the closed voltage to .67vdc. I also switched out PCM with the same tune I have been running for a year and it does the same thing. About the third I start it up is when everything goes back to normal. I start it once and it idles high and throws a low tps volt code. Shut it down and start it up again; same thing. I usually let it run about 30 seconds each time. The third time I start it up everything is fine again. I want to say it's right about the time the car starts to warm up is when everything goes back to normal. Any ideas?
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Could be something sporatic in the TPS wiring, I suppose. It indeed seems odd that the voltage reading stays the same, but the % the PCM translates it to is not always the same. Try adjusting for a lower closed throttle voltage and see if there is any change.