Andy.F

How is the Idle Speed Control valve operated ? It has 3 wires to it (MY95) Is it a PWM solenoid or stepper motor or ????
What I need to know is how can you drive it full open ?
When I disconnect the plug the engine idle becomes very rough
If it was PWM I would expect it just to close ?

Andy

Pavlo

It appears to be either just an armature, or a stepper driving a magnetic coupling. If you take the top off you will see it doesn't connect to anything, so the shaft is just magnetically coupled.

Are you wanting to do something with it along the lines of an ALS system?

I'm not sure how it's driven, but would also like to know, as I'm now looking at putting the phase 2 manifold on my car with some matching heads.

Paul

Andy.F

A very basic form of anti lag I guess. Just to assist between gearshifts I was going to connect the ISCV inlet to the IC outlet, connect the drive to a button on the gearstick, then when changing gear under full acceleration, press the button to keep some airflow/power on closed throttle. The intention being to assist the turbo stay up to speed.
Similar effect to not coming fully off the throttle between shifts, I've always had a mental block with doing this !!
Flat shifting on the rev limiter is another cruel option but the clutch would just vapourise on my car
Ideally, the flow through the ISCV would be just enough to keep the rpm floating around 6k between gear shifts.

Pavlo

possibly with lots of fuel and zero degrees advance

ustolemyname??stevieturbo

iTrader: (1)

Phase 2 manifold uses a stepper motor. It is not the same as the earlier manifolds ISCV

Pavlo

This I now know, thing is, how to work with it.

I'm assuming the pre97 type is a PWM (pulse width modulation) servo motor, with just a power, ground and PWM signals.

TO take control of it would be easy ish, you would need a switch to switch the idle switch on the throttle body on or off, then feed a PWM signal, but maybe even 0 or 5v will just put it at one extreme or the other.

Phase 2 has 6 connections, so I'm thinking ground, 4 coils and possible a feedback pot. I'm wondering if I can use a PWM -> stepper control board somehow to allow the ecu to control it. some how plumb in a bypass that connects to the stock ISCV located remotely somewhere.

Paul

Scooby Racer

Just send 12v down either side drive wires of the solenoid to close or open the valve. No voltage applied and the valve sits around the half open position, which can be adjusted by moving the coil on top on the mounting slots.
The valve as standard doesn't give all that much flow, you really need to open it up from the base plate and remove all the temp compensating parts to improve the airflow. I can't remember exactly the details of stripping it so suggest using a knackered one as a test piece.
If you were thinking of removing all ECU control from the ISCV you will need to jack open the throttle on the idle stop to allow the engine to idle.

Andy.F

Thanks for that

Andy