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Does anyone know how to manually adjust the TPS to make sure I'm actually at WOT when the pedal is all the way down? I read that it could be as simple as turning a screw to make sure I'm at full voltage at WOT. Thanks for any help!

Drew
 

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BumpinGTP said:
loosen the two screw holding down the TPS sensor, the turn the sensor until the voltage reaches its highest point. tighten the screws again.
I heard there was a range that the voltage should lie between, not just the highest voltage... Do you know anything about that? What tools will I need besides a voltometer?
 

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if you have autotap or LS1m these can be used. scan the TPSV and TPS. i believe my voltage is somewhere around 4.6 with the car off and key in on position.
 

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I'm assuming since yours was 4.6, that the TPS voltage is similar to what we see on LS1 cars. I also have a 00' SS M6 btw.....473 rwhp. :D But anyways, we like to see at least 4.6, with no more than 4.7 ;)
 

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What kind of voltage should be at minimum. I always saw .4 volts with my stock setup with the throttle plate fully closed. .5 with my N* setup, but thats with an Electrical gremlin i'm fighting.
 

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BumpinGTP said:
my LS1 t/b show .45 volts when closed at 0%
With my LS1 TB I see .44 at 0% and 4.78 at 100% I believe 4.75 and greater is WOT.
 

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On an LS1 TB, you don't want to go more than 4.7 @WOT. ;) It looks as if you guys are dead on. :)
 

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Hopefully I can help clear some things up :) That's my writeup linked to, here's a more up to date version http://www.oqcgp.com/forum/kb.php?mode=article&k=33

LS1 WOT TPSvoltage will vary based on the infamous bump stop milling, but most ZZP units come with low 4.8x voltage.

LS1 F-Body's can't exceed 4.75 WOT volts without throwing a code, our cars don't do that til 4.9 volts.

Our PCMs will commant WOT at around 4 volts, maybe 4.1, I forget the exact number. The LS1 TBs will reach this voltage faster but the WOT voltage is hard coded in the PCM and remains unchanged.

It is a bad idea to tune based on idle TPS voltage, without relating it to WOT voltage. Reason being is that the idle stop screw makes this a variable instead of a constant.

Stock throttle bodies are around .4/4.1 voltages, and are best tuned to 4.32-4.34 WOT voltage, along with 10-15 IAC count at idle (while not exceeding .75 volts).

LS1s I like to set up around 4.82-4.84 WOT voltage, but will usually only touch the TPS sensor if it is too close to 4.9 (eg 4.88). Idle stop screw adjust to 1/4 turn preload on the linkage, just enough to stop and binding in the inner bore. To help idle out, enlarge the IAC slit between the TB and the adapter, as Brent H and I show in the instructions on ZZP's site. Then drill the hole back in the throttle plate to at least original size, larger if hard starting still exists.

I don't have any GP testing of the Northstar TB but my mother's 96 STS Northstar I have set at 4.67 WOT voltage with a .71 idle voltage. I couldn't get an IAC count reading off my Alex Pepper scantool but the car responded well.

HTH and please email or repost if I can help clarify :)
 
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If I loosen the nut, which way do I turn the screw to make the idle voltage lower? My voltmeter was not working right last week when I went to do this and I had to guess where to set it.
 

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hey guys. my TPS is reading 99.6. is that ok or should i get it to 100

thanks
Jon G
 

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I did this mod the other day, and suffice to say, throttle response has definately gotten better. I need to autotap to see whats going on and possibly tweak it out some more.
 

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Don't close the TB blade too far, it will stick when the car is cold...FYI.
 

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Ron, when i first set it, I set it to 4.32 WOT and it just happened to fall on about .72 idle voltage without me have to adjust the nut underneath, is that ok?
 

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Got me, I haven't tried to tune the TPS. When I change out a TB blade (even if it's stock) I just set the set screw out enough not to affect IAC values, or someone will be calling me back about how his TB is sticking. My personal TB reads .4 at idle and 4.1 at WOT.
 

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10-15 is about what you'd see on a ported TB, stock it's higher out of the box. More like in the 40's. The IAC becomes unshrouded on a ported TB, thus the lower counts.
 
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