PWM Idle Dashpot???

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superchargingmachine
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PWM Idle Dashpot???

Post by superchargingmachine »

I am about to start experimenting with PWM idle. In rereading the help section in Megatune I realize I never quite knew what Dashpot was or is? Is this an input or an an event? A simple explanation will probably get me or the hump:=)
Keithg
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PWM Idle Dashpot???

Post by Keithg »

'Dashpot' as referred to in the docs for closed loop idle is an algorithm that mimics a throttle dashpot (damper). Basically, closed loop idle closes teh dashpot for maximum engine braking when you come back to idle, it needs to open up the AIC to regulate idle. Currently, it uses the last valid idleDC and adds a few more counts to it (what we calle the dashpot) and waits for the idle to settle out (dashpot settling time).

hth,

KeithG

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superchargingmachine
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Post by superchargingmachine »

Perfect explanation thanks! I have never heard that term for some reason but I have seen the mechanical version.

BTW - Just got my Ford PWM valve working today and surprisingly it only took a few minutes to get tuned. It may not be perfect but it is close.
Keithg
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PWM Idle Dashpot???

Post by Keithg »

great to hear! Some have struggled, others have it going. I have been running it for a while.

KeithG

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superchargingmachine
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Post by superchargingmachine »

Let me retract that. I just upgraded to 29q2 and now I am struggling with PWM settings.

I'm using a mid 90's Ford valve on a Toyota 1.6L 4A if anyone has settings they know work but I suspect this is going to be engine specific.
Keithg
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Post by Keithg »

please post more details. if you can screen cap the pmw settings pages, that would help and a note about what the problem is.

keithg
superchargingmachine
Experienced MS/Extra'er
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Location: Illinois, Central

Post by superchargingmachine »

I will post my settings tomorrow. Funny tho I was playing with the PWM settings trying to get rid of the hunting then the idle control just stopped working. I probably changed a setting wrong. I hope I didn't burn something out.

I am done for the night. I just read the thread "MS1 Pwm Idle does not work." and have some ideas for tomorrow.
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