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I use 2 wires Bosch style ISC in 2jz turbo , notice that ECU still gives PWM that makes ISC stay open even when engine and vehicle speed at above the lockout area. This happens either open or close loop  sol mode. At open loop mode the PWM %DC will = setting value, when in close loop mode the %DC stay at the last value before it pass lockout setting. Is this normal?

Is there anyway to close the ISC after passing the lockout values to prevent boost leaked from ISC

Fury_2jz_rev2.pclr

CL isc vs vss.llg

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On 11/9/2018 at 6:10 PM, FIS said:

I use 2 wires Bosch style ISC in 2jz turbo , notice that ECU still gives PWM that makes ISC stay open even when engine and vehicle speed at above the lockout area. This happens either open or close loop  sol mode. At open loop mode the PWM %DC will = setting value, when in close loop mode the %DC stay at the last value before it pass lockout setting. Is this normal?

Is there anyway to close the ISC after passing the lockout values to prevent boost leaked from ISC

Fury_2jz_rev2.pclr

CL isc vs vss.llg

The idle valve remains active at all times, this is normal otherwise you would feel it switch on/off during normal driving.  

With an NA engine you can have one side of the valve vented to atmosphere but in a turbo application the valve should be connected to the manifold on one side and the turbo pipework on the other so both sides of the valve are exposed to a similar pressure under boost.

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On 11/11/2018 at 8:03 AM, Adamw said:

The idle valve remains active at all times, this is normal otherwise you would feel it switch on/off during normal driving.  

With an NA engine you can have one side of the valve vented to atmosphere but in a turbo application the valve should be connected to the manifold on one side and the turbo pipework on the other so both sides of the valve are exposed to a similar pressure under boost.

Dear @Adamw,

So are you saying it is normal for the ISC to remain active all the time? if that's so why does it have a function of Speed Lockout? Isn't this function to disable the ISC when it passes the speed that we set?

image.png.fae6adf131232cc0c060f2ccf3dbc1f7.png

Note:

  • I am using a 3 pin isc from 3sgte st246 Caldina Engine. i've got not problem with the idling. Idling is running well and good.
  • Speed input was set to Non Driven wheel. I connect from the VSS (gearbox) to the D1. The reason i set to Non Driven Wheel because to take advantage of Engine Fan speed lockout.
  • I can see my ISC Solenoid still in 'ON' status even though it has passes the 5kph Speed Lockout.

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To confirm Vaughan's comment, the lockouts just control the point at which closed loop control takes over.  Outside of the lockouts the idle valve will be in open loop mode and will just follow whatever is in the base position table.  The help file explains how most of these functions work.

ZswBe8v.png

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