MS3X 100% idle duty cycle
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MS3X 100% idle duty cycle
So I'm working on getting my '00's idle sorted out on my ms3x. However, it is taking 100% idle duty cycle to get the car to even idle at 850 or so rpm. I cannot seem to make it idle any higher (Falls to a very rough idle at 600 or so rpm when A/C is cut on). Why am I having to use such a high duty cycle to achieve this idle?
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I do. 1N4001.
I don't have TunerStudio available atm, but looking at the raw msq file, I believe it is set to 511Hz.
Code:
<constant name="pwmidle_freq_scale">"511Hz"</constant> <constant name="pwmidle_freq_pin">"Idle"</constant> <constant name="pwmidle_freq_pin3">"Off"</constant>
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EDIT: Also attached my pinout, just in case.
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looks like they changed the firmware on my, what's the PID Gains? and why are you on basic and not using PID?
I guess you can go 2-turns CCW on the TB and see if you can manipulate the idle better. you should have an almost 3K swing from about 20 to 60%DC.
I guess you can go 2-turns CCW on the TB and see if you can manipulate the idle better. you should have an almost 3K swing from about 20 to 60%DC.
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This is using MS3 1.3.2 Beta firmware.
I can turn the TB screw and try that, but until I get alternator control sorted I keep having to swap back to the stock ECU, so just one more thing I'd have to remember to change in the event of ever needing to run the stock ecu during my initial megasquirting adventures.
I'll try and look for the PID gain here in a few minutes.
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It has to be. Idle valve test DOES change the idle, just not significantly. Maybe like 200rpm from 50% to 100%
It's not exactly what I'd call pretty, but here is a picture of the diodes confirming the idle diode IS in place (ignore the extra pin I caught in the shrink tubing. I'll fix that, it's VICS anyway, not idle.
It's not exactly what I'd call pretty, but here is a picture of the diodes confirming the idle diode IS in place (ignore the extra pin I caught in the shrink tubing. I'll fix that, it's VICS anyway, not idle.
Last edited by Schuyler; 06-24-2014 at 02:20 PM.
#19
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I turned the TB screw a little, and now I can idle up to around 1300 at 100%. I'm still having issues getting the car to idle though. Cold start: needs throttle assistance to stay going, and stalls without it at the first stop sign or two leaving the subdivision. If I drive for a bit, and come to a stop, it starts idling at like 400, then creeps up to where it should be, almost like it's predicting the wrong duty to start with, and corrects it. I'll have to look in to that.
Instead of making a new thread, I'll throw a few more things in here:
Fan is always on, even though tunerstudio says it should be off. No idea what's causing this.
RPM (Cam?) signal loss at 4500rpm. Tach freaks, alternator light comes on on the dash. Car behaves like fuel cut. From what I've seen you say on another thread though, I should be able to fix this by adjusting the pot on the Xpansion board.
Other than that, AFRs look solid for what driving I've been doing. Just need to get the cam signal fixed, figure out how to get the idle tuned properly, and fix the fan issue. Any suggestions on the above are greatly appreciated.
Instead of making a new thread, I'll throw a few more things in here:
Fan is always on, even though tunerstudio says it should be off. No idea what's causing this.
RPM (Cam?) signal loss at 4500rpm. Tach freaks, alternator light comes on on the dash. Car behaves like fuel cut. From what I've seen you say on another thread though, I should be able to fix this by adjusting the pot on the Xpansion board.
Other than that, AFRs look solid for what driving I've been doing. Just need to get the cam signal fixed, figure out how to get the idle tuned properly, and fix the fan issue. Any suggestions on the above are greatly appreciated.
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1. the idle is just messed up. why, i dunno. A fully opened idle valve should shoot the idle to around 3000RPM. I don't think it's software related though.
2. messed up your wiring or settings.
3. tune your cam zero-point pot (should have been turned at least 3 full turns CW)
2. messed up your wiring or settings.
3. tune your cam zero-point pot (should have been turned at least 3 full turns CW)