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After trying a lot of diagnoses and swapnostics finally come to the conclusion that it’s not going into closed loop idle due to the tps voltage not dropping below 0.7v even though tuner pro is showing 0%. We’ve modded the tps to have slots in it and adjust it but the minimum we can get is still only 0.7v. Is there a scalar that hasn’t been defined for closed throttle voltage that could be adjusted as the only other thing I can think of it putting a resistor in the 5v ref line and drop the total voltage to the sensor by maybe 0.5v to 4.5v just to get it into closed loop
Any thoughts

A pull-down resistor might be the best idea instead of inline. Try a 5 or 10k resistor between the reference and ground to see if that drops it low enough at idle. It may adjust the signal curve a little away from linear but as far as I know the signal is mainly used for accelerator enrichment with a rate of change. If 5k is not low enough try 3.7k, 2.7k, 2.2k or a small trimpot. Get a reading from the trimpot , then swap it with a fixed value resistor.

Use a scope or multimeter to check the values at other throttle positions, with the engine not running, to see if they are not badly effected.

ended up trying the pull down resistor and it dropped the voltage to 0.3v but only reached 50% throttle and still didnt end up entering closed loop idle. i ended up finding a parameter called tps hysterisis and adjusted that up from 3 counts to way too much for starters and it entered closed loop but would drop in and out at low rpm and tps now adjusted it back to like 6 or something and seems to be better whilst entering idle perfectly now. im unsure of what this parameter is actually looking at to operate though anyone have an idea?

im a bit late to this thread so sorry if I missed something but on this, the TPS is auto calibrating, it adjusts its idea of 0% and 100% on the highest and lowest voltage it sees. But there are some scalers to adjust some limits. I doubt its actually voltage that is tripping you up here. Have you looked at the scalar TPS - TPS Closed throttle threshold?

I did try that setting along with just about every other parameter under tps/iac and idle but nothing seemed to work until I tried adjusting the “tps hystersis” setting I’m guessing it’s wanting to see a certain amount of iac counts drop at 0% throttle close to activate closed loop? But after adjusting that it ended up in closed loop idle with no issues and if it was to high counts in the setting it would try and enter closed loop at even low throttle openings while cruising.