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Discussion Starter #21
No, I never have adjusted anything.
I had someone adjust it when I first got the car, and Paxton installed back in 2000. I wasn't to familiar with the way everything was supposed to operate, at the time.
Should I lower TPS voltage to 1 volt, and back out the stop a full turn ?
 

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the TPS is not adjustable

the throttle stop must be in a very specific place, its not a matter of listening a change

the throttle body must flow the air its been calibrated by ford

you can crudely with little chance of working,

get the engine nice and hot

pull the spout and IAC connector, back the stop until it barely idle or even stalls

erase the KAM, disco the battery, 10 mins

reconnect spout and iac and start, let idle on its own, it may die, just restart

maybe it will idle properly, then check that tps is between 0.65-1.15 volts, if so its good
 

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based on OP, the idle climbs after the car warms up. something is changing after it's warmed up, most likely the TPS resistance. they do fail.
 

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It does sound like the the TPS voltage is changing, but i am chalking that up to incorrect testing at this time
 

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Discussion Starter #25
It does sound like the the TPS voltage is changing, but i am chalking that up to incorrect testing at this time
I did what you explained, and TPS voltage did drop down, to 1.2 volts.
The TPS looks like, the mount holes, have been reamed. I turned the TPS module, and voltage is reading, 1.09v. Disconnected battery and going to let it cool down for a bit.
Appreciate all the help! These adjustments are making an improvement .
 

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89 347 x303 cam scat stroker
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Cold start, idles great.. stock 5.0 long block, 6psi Paxton SN2000, base line timing at 6 degrees.
The car, cold starts and idles great, once it gets warmed up the idle starts to climb, like a high idle setting on a carburetor.
I set the TPS voltage long ago at 0.96, haven't touched it since.
Has A9L PCM, and no trouble codes.
Is this normal because of blower?
Car runs well, the way it's set up, just the quirky high idle, at operating temp.
Thanks for the help everyone!
Don't forget about testing the CTS coolant temp sensor o_O
 

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I did what you explained, and TPS voltage did drop down, to 1.2 volts.
The TPS looks like, the mount holes, have been reamed. I turned the TPS module, and voltage is reading, 1.09v. Disconnected battery and going to let it cool down for a bit.
Appreciate all the help! These adjustments are making an improvement .

so the stop was opened by someone in an attempt to raise the idle, which is counter productive as the ECM is going to go into rpm lock out

iac is going to be closed and spark is going to drop

as a result the engine will surge and easily stall as it chases its tail
 

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Discussion Starter #28
so the stop was opened by someone in an attempt to raise the idle, which is counter productive as the ECM is going to go into rpm lock out

iac is going to be closed and spark is going to drop

as a result the engine will surge and easily stall as it chases its tail
I drove it to work today, it's only a 4 mile commute of city driving. It ran and idled around 850 900 RPM.
( Got an old VDO Tach, I'm going to install soon.)
It ran well, on the way home, the MIL light came on, I checked it right away, and it was Code 91 lean condition, should I turn the stop in a touch
 

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no

you should address the code

the money you wasted on a tach, could go to a device that can help you tune a datalog real time

stating idle rpm, without knowing desired idle commanded by ecm is useless information

factory tach is MORE than adequate
 

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Discussion Starter #30
no

you should address the code

the money you wasted on a tach, could go to a device that can help you tune a datalog real time

stating idle rpm, without knowing desired idle commanded by ecm is useless information

factory tach is MORE than adequate
I've had this after market Tach for 20+ years, figured it'd be a little more accurate. Factory tach, sticks at times. I will keep a check on this lean condition, first time I've seen this code.
 
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