MS2 EBC sort of working
#1
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Now that I have the MS2 up and running smoothly (with the idle valve unplugged but that is a whole other problem) I have spent a bit of time trying to set up the EBC. it is sort of working, but I thought you guys (looking your way brain) would be able to shed some light on the issues that remain.
It is wired inside the MS as per the diy writup on this forum. I can set it to open loop and it sits at 14psi just fine. I have been setting the wole duty cycle table to the same figure as I am not really planning to use it long term and just wanted to make sure it was working. With polarity set to normal 20 gives 14psi and 40 bounces off the OBP limit. SO flipped it to inverted and set at 80. I get 14 again.
Then switched to Closed loop with the pid gain set to 150 and it bounces off the OBP limiter again, Bumped the gain up to 185, and eventually 200 and it calmed down a bit. Lots of oscillation coming up to boost and then hits the limiter again. All the tuning guides I have read say that 150 should be plenty so is there something wrong here? This is with the valve that diyautotune sells and the freq set to 19.5 Hz. Wired with the output from the MS, going thru a 3 amp micro toggle, then out to the valve. The other side of the valve wired to the 12v source at the blue plug behind the L/F headlight. and the diode at the valve as per the writup here.
All that sound right? anything I am missing? or should my 1st PID gain box really be 200+?
It is wired inside the MS as per the diy writup on this forum. I can set it to open loop and it sits at 14psi just fine. I have been setting the wole duty cycle table to the same figure as I am not really planning to use it long term and just wanted to make sure it was working. With polarity set to normal 20 gives 14psi and 40 bounces off the OBP limit. SO flipped it to inverted and set at 80. I get 14 again.
Then switched to Closed loop with the pid gain set to 150 and it bounces off the OBP limiter again, Bumped the gain up to 185, and eventually 200 and it calmed down a bit. Lots of oscillation coming up to boost and then hits the limiter again. All the tuning guides I have read say that 150 should be plenty so is there something wrong here? This is with the valve that diyautotune sells and the freq set to 19.5 Hz. Wired with the output from the MS, going thru a 3 amp micro toggle, then out to the valve. The other side of the valve wired to the 12v source at the blue plug behind the L/F headlight. and the diode at the valve as per the writup here.
All that sound right? anything I am missing? or should my 1st PID gain box really be 200+?
#7
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sounds and looks you you have it correct.
you have you wastegate duty open at 100 and closed at 0 with te polarity set to inverted?
what is the code doing with the duty cycle? Are your closed loop targets tuned? With a 200 P, the code should be keeping the duty fully clamped, no boost entering the wastegate, and as it nears it should fully open going straight to wastegate. As you lower P it should start reaching the boost target.
you have you wastegate duty open at 100 and closed at 0 with te polarity set to inverted?
what is the code doing with the duty cycle? Are your closed loop targets tuned? With a 200 P, the code should be keeping the duty fully clamped, no boost entering the wastegate, and as it nears it should fully open going straight to wastegate. As you lower P it should start reaching the boost target.
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here is what I have now. This worked pretty good and sits right at 14 psi. Drop the dc to 60 and it hits the limiter.
![Name: openloop.jpg
Views: 161
Size: 79.8 KB](https://www.miataturbo.net/attachments/megasquirt-18/188249d1501218526-ms2-ebc-sort-working-openloop.jpg)
This however is borderline useless. The boost comes up to around 12 psi, then oscillates up and down 1 psi, creeping higher each time, and hits the OBP limiter about the 5th time. the higher I set the P Gain, the more controlled it gets but at 200 I figured something was wrong and stopped playing with it.
![Name: openloop.jpg
Views: 161
Size: 79.8 KB](https://www.miataturbo.net/attachments/megasquirt-18/188249d1501218526-ms2-ebc-sort-working-openloop.jpg)
This however is borderline useless. The boost comes up to around 12 psi, then oscillates up and down 1 psi, creeping higher each time, and hits the OBP limiter about the 5th time. the higher I set the P Gain, the more controlled it gets but at 200 I figured something was wrong and stopped playing with it.
![Name: closedloop.jpg
Views: 150
Size: 83.5 KB](https://www.miataturbo.net/attachments/megasquirt-18/188250d1501218526-ms2-ebc-sort-working-closedloop.jpg)
#10
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Ah, I think I changed that to get the duty cycle vs boost relationship correct as per the ma2exta manual writeup. But to be honest I don't remember. I'll flip it back around and try again in a couple if days (its raining now so can't test today). Thanks man.
#13
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Changed it and still no joy. Made pretty much no difference. Just came across somthing on another thread regarding the tps. I have a real one in there, Variable, does that make any difference? is that what the closed and open duty cycle values are relating to?
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