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Old 09-30-2016, 05:04 PM   #21
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Also, I got more information about my idle issue that I was having. Basically, it would oscillate up over 2k after driving for a few minutes whenever I put the clutch in. Got to the point where even after 15 minutes of driving, it was still doing it until I left the clutch in or put it in neutral and didn't touch the gas for 10-15 seconds. Then it would settle down and run normally.

I noticed that the oscillation was being cause by the fuel-cut activating at 2k while it was revving up on it's own (once again, in neutral or clutch in, no throttle). So my idle control is revving the car up unnecessarily, but then fuel cut comes in and stops it.

My question is this:

Is there some sort of trigger that needs to be met (condition) to stop the car from trying to idle up? The car is 100% warmed up in this case, but still idling up like it's cold. IF, and this may help, I let the car warm up for 1-2 minutes before driving when first starting it, this issue does NOT take place. But if I crank it over, wait 5-10 seconds, then start driving, happens every time. So in my mind, the MS3 never figures out that the car is done it's warmup even though CLT is in it's happy place (200 or so). WUE and ASE are both not enabled when this condition occurs. The logs I posted way earlier in this thread demonstrate the issue but don't show the fuel cut taking place, which it is.
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Old 09-30-2016, 09:38 PM   #22
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I believe I have the exact same issue and that it is the same one mentioned here: MS3 PID Idle Target - Why does it change when returning to idle? . As you mentioned, when the car is cold, it will go to the proper target closed loop idle target for the corresponding CLT. However, as the car is warming up, the Closed Loop Idle Target keeps jumping up by 300-400RPM every time the car is placed into neutral. Then, you have to wait 5-10 seconds in neutral for the Closed Loop Idle Target to ramp down to the desired 850RPM for CLT > 180degrees (or whatever the corresponding RPM for your current CLT is).

If you encounter a lot of stop signs on the way to your destination (like I do to work), the car never sits in neutral long enough for the Closed Loop Idle Target to ramp all the way down to 850RPM. You end up with a Closed Loop Idle Target jumping up 300-400rpm every time you push the clutch in (which results in an idle RPM of ~1800RPM), until you finally sit in neutral long enough for the Closed Loop Idle Target to go down to 850RPM (i.e. the red light outside my work). I took a good log of this happening a few days ago and can upload it if it'll be of help to solving this issue. Sorry I don't have an answer to this yet.
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Old 10-01-2016, 09:29 AM   #23
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Same issue. Would love to hear the results if you ever get it fixed.
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Old 10-01-2016, 11:09 AM   #24
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A possible solution on the Enhanced MS3 would be to switch to open loop idle, and then rely on the electrical load idle-up and the power steering idle-up functions of the Enhanced MS3 to compensate for any loads.
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Old 10-04-2016, 08:58 PM   #25
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Unfortunately I have the MS3 Basic but that might be a good solution for OP. I'll have to see if changing the over-run fuel cut RPM has an effect on my problem as well. It's really only a nuisance when the car is warming up but I'm still wondering what actually is going on.
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Old 10-04-2016, 09:08 PM   #26
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For closed loop activation try changing between "use last value" vs the CLT/iat initial values and see what happens. Also pid settings.
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Old 10-04-2016, 09:34 PM   #27
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Quote:
Originally Posted by TheIglu View Post
Increasing the priming pulse and bumping up my ASE did the trick. Typically it does a crank-sputter-sputter-sputter-die or crank-sputter-sputter-revtothemoon for 5 seconds then settle.


This morning was the first time in months that it fired up normally when cold. I'm happy and will continue to tune.


I wish there was a "A-Z, installing your MS2/3 and getting it to run alright" thread somewhere. The magic "most of our cars need 200-300% ASE" statement I read yesterday on a random thread here was the tidbit I needed to fix my nagging issue.
Hmmm. My MS3 only allows for a max of 50% ASE. 200%-300% seems an awful, awful lot of additional fuel. Are you sure that you're giving more than 2 times the required fuel here?
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Old 10-05-2016, 11:20 PM   #28
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I misspoke, priming pulse is what I was talking about. ASE is not anywhere close to that.
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Old 10-05-2016, 11:30 PM   #29
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You guys think this might have something to do with it?



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Old 10-06-2016, 02:53 AM   #30
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No.

Another solution that works well for me is to lower the closed loop targets and the PWM idle cranking duty.

Like 1000rpm target from 25-30 onwards, with the cranking duty to match that target + 2%.
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