Hesitation when throttle is jabbed quickly - S1 TPS in S2 R33 RB25

[kleb420]

hey there guys

have been a long time reader but first time posting

i have recently had my 96 S2 R33 with RB25DET at the tuner after a bunch of new mods

he was having an issue with the car hesitating for a second or 2 when the throttle is jabbed quickly.. making it feel quite un responsive and laggy ( throttle is fine otherwise, just has to be increased slowly.. its most noticable down low or when giving it a quick rev in neutral)

he believed it to be a TPS issue so i got a new NISSAN TPS the same as what i had in the car. which surprisingly was a S1 TPS (obviously with a S1 Throttle body too, installed by previous owner) with the extra plug and fly lead hanging off it.... he managed to tune it ok but it still has the same issue - just to clarify ive got it plugged into the fly lead plug not the one on the bottom of the sensor.. i believe this is the signal plug

so this is a two pronged question

1. other than the way the the TPS mechanicaly connects to the throttle body are the sensors both the same electronically? 0.5 - 5v DC? - if so it shouldnt matter that i have a S1 sensor on a S2 motor

2. when i tested it i seem to be getting 0.6v at closed throttle and 3v ish at WOT.. i believe its ment to be 0.5 - 5v from what ive read on SAU.. i have hesitated to adjust it as dont want to screw up the tune i have just had... but is this likely to cause the problem i am having.. or is it possible he has compensated for these incorrect voltage readings in the ECU (VIPEC) or something?

 

any assistance would be greatly appreciated.. and ive been searching for a couple hours and couldnt find anything that answers this completely.. so sorry if this is a repeat post

thanks

caleb

Edited June 4, 2018 by kleb420

[89CAL]

If you have a VIPEC you can watch the TPS voltage on your laptop. You can also do a TPS calibration with the VIPEC software. You should be able to see if is seeing the throttle at 0% closed and 100% at Wide open throttle. If this is the case it wont need calibrating

Take it back to your tuner?

[GTSBoy]

Yuh, if it was a factory ECU I would have said TPS adjustment 100%.  Because it's aftermarket ECU, there is nothing stopping you/the tuner from adjusting it either in the ECU or in the engine bay.  In other words, the tuner shouldn't be having any trouble with the new TPS if he set it up as he installed it, like he should have.

[kleb420]

ok thanks heaps guys will get on the laptop tonight and see what readings im getting and report back ?

 

[kleb420]

ok think ive worked it out. checked it on my laptop and it confirmed the voltages i was reading... range was 1.4% at closed ant 99.8% at WOT... but i dont think that was the problem.. when i loosened the TPS i could move it alot without the ECU getting a change in %... so i believe its because the shaft on my TB is a bit smaller than the inside of the TPS.. bit of foil tape around the shaft and its much better also re calibrated the TPS % in the ECU so all is well now.. not 100% but very close

 

thanks for the imput guys

caleb

[sonicz]

Too high or too low fuel pressure can also cause this im addition to the two step voltage the ecu is able to provide the fuel pump. If its a  aftermarket one it wont flow the same as stock on low/high voltage switching.

Thats what it was for me and it had nothing to do with tps

Edited June 16, 2018 by sonicz