Brain MS3X Idle 'Issues' (Idles at 3k)
#101
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1.4.1 didnt have engine states. They are the backbone of the tune. Used for cl idle, idle ve, idle timing, overrun, etc.
Here is my best guess on how to tune engine states. Waiting on confirmation from Ken. And tuning them myself.
Fast acceleration threshold: Some low gear, step on the throttle. Pick the lowest(?) RPMdot while accelerating. Set the fast acceleration threshold just below that?
Slow acceleration threshold: Datalog idle and see what the highest RPMdot is during idle. Add and remove loads to get rpm changes. Set to just above the highest RPMdot at idle
Fast deceleration threshold: Rev high in neutral and let it drop back to idle. Set it slightly above the highest RPMdot from that test.
Slow deceleration threshold: Same as Slow acceleration threshold, but with negative RPMdot
TPS: Pretty self explanatory, value when tps is closed, and when full throttle
Overrun Map Threshold: Set as high as possible, I usually use a MAP value just under the lowest MAP I see on idle.
Here is my best guess on how to tune engine states. Waiting on confirmation from Ken. And tuning them myself.
Fast acceleration threshold: Some low gear, step on the throttle. Pick the lowest(?) RPMdot while accelerating. Set the fast acceleration threshold just below that?
Slow acceleration threshold: Datalog idle and see what the highest RPMdot is during idle. Add and remove loads to get rpm changes. Set to just above the highest RPMdot at idle
Fast deceleration threshold: Rev high in neutral and let it drop back to idle. Set it slightly above the highest RPMdot from that test.
Slow deceleration threshold: Same as Slow acceleration threshold, but with negative RPMdot
TPS: Pretty self explanatory, value when tps is closed, and when full throttle
Overrun Map Threshold: Set as high as possible, I usually use a MAP value just under the lowest MAP I see on idle.
#102
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I have had VSS not be overly accurate, at least not on an NA with a mechanical sensor. I wouldn't use it for anything except for knowing a rough speed you are going.
NB might be different and better.
NB might be different and better.
#103
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So if I enable VSS and set speed to say 5 mph, which is what I tried yesterday, it won't kick into idle till I slow down that much. I can see this potentially being an issue in a situation where I'm slamming on the brakes (getting cut off maybe?), so I might raise it to 8 or so. I'm guessing the MS needs like a split second to trigger idle and if the idle valve setting is close enough it should bump right up.
I'm going to write down all of those and do a log when I go out tonight. I think the car is working well enough now that I can drive it around, so I'm going to start taking it to school with me so I can take a study break and go tune things instead of reading about them and/or go drive a local loop on the way home to get more data. I'll post the 2 giant logs and tune from last night when I get on my surface so you can check those out and see if there's any info in there that satisfies your curiosity.
Unrelated to anything, if virtual dyno is smart enough to use the best pull in a large log, then apparently I'm sitting at 110ish whp and 100 wtq. Lulzzzzz. My goals for the turbo setup are to double the stock hp. I think I'll be able to do that and keep my stock engine happy hahaha.
I still haven't deleted/modified the stock air intake so I'm guessing things could be a lot better than they are. Also fueling needs to be optimized a bit. I feel like I should be seeing a higher number right now though. I also used 2450 as the weight which might be like 200 lbs low because my gas tank is full, the car has a roll bar + heavy wheels + donut, and I weigh like 170. I'm curious what the 'actual' weight is closer to... I think the stock 2000 weighs like 2332 or so, but I'm guessing that's without a full tank of gas.
Edit: I think the 2332 weight is the curb weight that includes all fluids etc for the nb1. I guess I just need to add like 200lbs for myself and the roll bar.
Last edited by ridethecliche; 04-18-2017 at 01:35 PM.
#104
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So if I enable VSS and set speed to say 5 mph, which is what I tried yesterday, it won't kick into idle till I slow down that much. I can see this potentially being an issue in a situation where I'm slamming on the brakes (getting cut off maybe?), so I might raise it to 8 or so. I'm guessing the MS needs like a split second to trigger idle and if the idle valve setting is close enough it should bump right up.
also, VSS stands for: vehicle speed sensor. Your terms are killing me
only triggering VSS below a certain speed.
#105
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Haha, sorry. I'm just going by how MS has it displayed under engine settings to enable VSS for idle/engine states.
Do you just adjust your Idle tables for loads you'd encounter at 80mph? I'm guessing it'd be a cruise load?
Do you just adjust your Idle tables for loads you'd encounter at 80mph? I'm guessing it'd be a cruise load?
#106
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Our idles don't change depending on how fast we are going. Seems like a silly setting, like Brain said I want my car to idle properly regardless of speed.
We tune our tables for every condition our engines encounter.
We tune our tables for every condition our engines encounter.
#107
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I guess I just don't understand why one would need to idle at 80 miles an hour.
I just drove the car around town for errands without my computer plugged in. Still had a hiccup with the battery light flashing on at low rpms once or twice, but it ran well. I'll do more logging later tonight. For now it's time to go to the library and hide from anyone with BUSM affiliations!
I just drove the car around town for errands without my computer plugged in. Still had a hiccup with the battery light flashing on at low rpms once or twice, but it ran well. I'll do more logging later tonight. For now it's time to go to the library and hide from anyone with BUSM affiliations!
#109
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And I spoke too soon about everything working well lol. Idle dipped low and was hunting real hard on a hot restart. My engine also sounds totally different than what I remember it sounding like. I mayyyy have an exhaust leak from when I moved things around to drill sway bar bolts.
#110
Fair enough! I guess it makes sense to have some cells way up there haha.
And I spoke too soon about everything working well lol. Idle dipped low and was hunting real hard on a hot restart. My engine also sounds totally different than what I remember it sounding like. I mayyyy have an exhaust leak from when I moved things around to drill sway bar bolts.
And I spoke too soon about everything working well lol. Idle dipped low and was hunting real hard on a hot restart. My engine also sounds totally different than what I remember it sounding like. I mayyyy have an exhaust leak from when I moved things around to drill sway bar bolts.
edit: nvm! I see you already did
#111
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1.4.1 didnt have engine states. They are the backbone of the tune. Used for cl idle, idle ve, idle timing, overrun, etc.
Here is my best guess on how to tune engine states. Waiting on confirmation from Ken. And tuning them myself.
Fast acceleration threshold: Some low gear, step on the throttle. Pick the lowest(?) RPMdot while accelerating. Set the fast acceleration threshold just below that?
Slow acceleration threshold: Datalog idle and see what the highest RPMdot is during idle. Add and remove loads to get rpm changes. Set to just above the highest RPMdot at idle
Fast deceleration threshold: Rev high in neutral and let it drop back to idle. Set it slightly above the highest RPMdot from that test.
Slow deceleration threshold: Same as Slow acceleration threshold, but with negative RPMdot
TPS: Pretty self explanatory, value when tps is closed, and when full throttle
Overrun Map Threshold: Set as high as possible, I usually use a MAP value just under the lowest MAP I see on idle.
Here is my best guess on how to tune engine states. Waiting on confirmation from Ken. And tuning them myself.
Fast acceleration threshold: Some low gear, step on the throttle. Pick the lowest(?) RPMdot while accelerating. Set the fast acceleration threshold just below that?
Slow acceleration threshold: Datalog idle and see what the highest RPMdot is during idle. Add and remove loads to get rpm changes. Set to just above the highest RPMdot at idle
Fast deceleration threshold: Rev high in neutral and let it drop back to idle. Set it slightly above the highest RPMdot from that test.
Slow deceleration threshold: Same as Slow acceleration threshold, but with negative RPMdot
TPS: Pretty self explanatory, value when tps is closed, and when full throttle
Overrun Map Threshold: Set as high as possible, I usually use a MAP value just under the lowest MAP I see on idle.
Did the method of testing for overrun MAP change? I.e. is it still supposed to be done by revving up high in a gear and coasting down? Or is it supposed to be done just on idle as above?
#113
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if your code waits for 5mph to engage the idle valve, you have probably already stalled.
#114
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I didn't stall. Not once. I did this like 10 times last night. I did get some unwanted idle behavior while completely stopped that I need to figure out. But I have logs for that.
#115
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Still not seeing the advantage to engine states. It also seems to me that to obtain the needed info to set up states, one needs an already tuned car.
And a +1 to idle and speed should be totally independent.
And a +1 to idle and speed should be totally independent.
#116
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It doesn't do that though. I'm not arguing with you about the practicality of what you're saying because it makes sense. But last night I put the car in neutral at 20-30 mph and braked to slow down at a light.
I didn't stall. Not once. I did this like 10 times last night. I did get some unwanted idle behavior while completely stopped that I need to figure out. But I have logs for that.
I didn't stall. Not once. I did this like 10 times last night. I did get some unwanted idle behavior while completely stopped that I need to figure out. But I have logs for that.
#117
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I wonder if the lower temps were messing with things too. I tuned in the 60's the first time and it was in the low 30's last night when I was driving around at 2 AM.
Brain, should I email you or post a video here of the fuel pump priming?
#118
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Fuel pump: Check for continuity to ground at the Fuel Pump diagnostic pin. Key off should be not continuous. Then it should go to ground while priming. Then be not grounded a few seconds later.
Bolded text will tell us if its Brain's fault or yours
Bolded text will tell us if its Brain's fault or yours