LT1-LT4 Modifications 1993-97 Gen II Small Block V8

P0123 Code - Holley 58mm is the cause

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Old Aug 1, 2009 | 08:57 PM
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Default P0123 Code - Holley 58mm is the cause

I went WOT the other day and threw code P0123 for high TPS voltage. I have heard that this is because my Holley 58 mm will spin past 90*. Are there any cures for this? Do I have to make some type of throttle stop to stop pulling this code?
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Old Aug 2, 2009 | 07:28 PM
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anybody?
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Old Aug 2, 2009 | 07:36 PM
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if it spins past 90 degrees then yeah, make a throttle stop. then it should stop throwing the code because it won't go out of the voltage range that is normal
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Old Aug 3, 2009 | 12:14 AM
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yeap time to make a throttle stop...
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Old Aug 3, 2009 | 01:31 PM
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Originally Posted by buffman
yeap time to make a throttle stop...
Any ideas on how to make one?
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Old Aug 3, 2009 | 01:41 PM
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Sorry to steal from you but what if its reading low TPS voltage??
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Old Aug 3, 2009 | 02:03 PM
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Many times with aftermarket TB's you have to slot the screw holes of your TPS and adjust it to read the right voltage at 0% throttle and WOT.
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Old Aug 3, 2009 | 06:00 PM
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Originally Posted by ss.slp.ls1
Many times with A TB's you have to slot the screw holes of your TPS and adjust it to read the right voltage at 0% throttle and WOT.
If I did that and moved the TPS sensor, wouldnt I then get a low voltage code? How do I measure what the correct voltage should be?
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Old Aug 3, 2009 | 06:03 PM
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Also what would happen if I just completely tuned P0123 off. Would this cause any problems?
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Old Aug 3, 2009 | 11:53 PM
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Originally Posted by ss.slp.ls1
Many times with aftermarket TB's you have to slot the screw holes of your TPS and adjust it to read the right voltage at 0% throttle and WOT.
That may be the case, but with Holley TBs they can and will open more than 90%. Various ways to make a throttle stop. I'll have to see if I can get my friend to snap a picture of the one he made for his holley. Ideally you want 0% TPS to be around .59-.7 volts, and WOT to be less than 4.8volts.
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Old Aug 4, 2009 | 01:24 PM
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Originally Posted by buffman
That may be the A, but with Holley TBs they can and will open more than 90%. Various ways to make a throttle stop. I'll have to see if I can get my friend to snap a picture of the one he made for his holley. Ideally you want 0% A to be around .59-.7 volts, and WOT to be less than 4.8volts.
Thank you very much! A pic would be awesome
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Old Sep 10, 2013 | 07:06 PM
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Could this cause the Trans to do some crazy shifting
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Old Sep 10, 2013 | 07:11 PM
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Originally Posted by Jimmy_d
Could this cause the Trans to do some crazy shifting
Untuned and you'll trash trans. Line pressure keys off TPS
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Old Sep 10, 2013 | 08:59 PM
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Originally Posted by buffman
Untuned and you'll trash trans. Line pressure keys off TPS
Ahh I figure it has smoked the 3 and 4 clutches .it randomly loses 3Rd and 4th
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