ISCV 20V confusion ...clean or not !

[mfauzi_s]

My experience...

U can see ur iscv clean or not. U need to open 2 pipe & see ur iscv valve clean or not. Normally iscv control engine warm up. Input voltage 12vdc. When u start ur engine, electromagnet will close valve slowly ( voltage 2 wire +/- 7v & +/- 6v sent signal to ecu ) and input voltage stay +/- 13v (alternator voltage). RPM from +/- 1300 to 950.

RPM 1300 = -7v & -6v
RPM 950 = -8.5v & -4.5v

If ur idle start low rpm (500 rpm), maybe signal wire cannot sent signal to ECU or open circuit. For 4age blacktop, ECU automatic up ur engine RPM in 4 minutes to normal idle not for 4afe.

Sorry. if i wrong statement.

 

[chinozie]

AE80TypeD - but how about "inside" that chunky metal thinggy...

have you open up the "star" screw on top left side of the picture ?

then peek a boo inside...

and yes...i believed (with my self learning, non-mechincal or technical background) , that the ISCV is not a sensor...plus it works on mechanical parts...thus...cleaning is ok...

how how...?



mfauzi_s - thanx for that...but we are discussing about cleaning the ISCV...can or can not...read the previous post...

 

[AE80TypeD]

its ok, mfauzi_s' info sounds like a useful thing for me to think abt, since i can find no physical fault with my engine or ISCV. maybe it is abt time i took a look at the signal side of things. im gonna need an electrician thank you for the info!

chinozie,
yes i have seen the inside view from the plenum side pipe. i cant say i understand things any better with that observation, but i guess i am now able to better imagine how the valve looks like. are u asking me to look for something for me to learn, or do u want me to show a picture of that view u described? it is as u said. everything in there is purely mechanical, springs, shafts, plates etc. im 99% sure that the parts are safe to be sprayed with solvents or cleaners. however i cant help wondering if the shaft between the pintel valve & its magnet-side interface is greased or fitted with bearings. im worried that if that shaft is greased, spraying solvents might not be such a good idea in the long run. i hope to god that the shaft uses ball bearings.

 

[chinozie]

ah haaa...

4AGE 20V uses Rotary solenoid...
so we can spray it...

after fully clean it...the rotating thinggy turnvery smooth and freely...niceeee !

BTW ...the old links didn't work anymore...as I've accidentally overide it...

Under certain circumstances…after cleaning your ISCV the idling still didn’t change much, it may due to other related things…
Which I can think of are :

1) ISCV magnetic part , the yellowish thinggy is totally condemned. Solutions : Replace you ISCV

2) TPS may need to be re-calibrate. Solutions : Will post on how to DIY it, or you may Google for it. Lots of page or Forum have discussed it.

or

3) ISCV wasn’t properly clean, still got a few residue inside. Solutions : Jeng jeng jenggggg !!! Please read more…Oyeh oyeh…

Here the newly updated page : :: [DIY] How to clean 4age 20v ISCV :: March :: 2008

 

[cuscostrutbrace]

Chin,

4ag 16v AE86 = Waxstat ISCV,AE92 not sure (maybe same as 86)
4ag 20v silver/black = Rotary solenoid
SUpercharger = Rotary solenoid

Normally rotary solenoid ISCV only have 3 wires,while stepper motor ISCV commonly 4 wires or 6 wires.The ecu will trigger the ISCV by duty cycle,means it grounds the solenoid open or close in controlled on and off action against preset time.Working principle same as VVT-i solenoid.It happens so fast we wont notice it.Duty cycle only can be seen on the osciloscope or special meter.I dont know how our friend mfauzi_s said he can measure the voltage according to the engine rpm,maybe he got some interesting method,i would like to know.If we disconnect the ISCV connector,the ISC Valve will return to a default position to let the engine idle,its a fail safe measure.

It is safe to clean because it is entirely mechanical,but after clean have to reset ecu and let it learn.I clean it once in a while,no problem with idling.

 

[chinozie]

Rahmat,

Thanks for the update...
at first i thought 20V uses stepper style...
then did some reading and found it out by opening up...found out i was wrong, my bad...it was rotary style...i've edited the first page and my blog... :D

For 20V ISCV, the yellowish thing (right side of the picture) always give up...as that's the who controlled the movement on|off and limited by the springging thing (left side of the picture) ...

to think about it...what mfauzi_s said...yaa man...i must be fun to read on the graph on oscilloscope...remind me off the school days ...check for noise, voltage leakage n what so ever that i didn't know much...

mfauzi_s - do you know how to play with oscilloscope aaa ? can find tune and check on few things...do you ?

 

[levin818]

Actually... you are not suppose to release the 2 screw and twist the valve.
The valve's default location is pre-set by factory.
Only the factory has a proper equipment to adjust it.
Once you touch it, it means, your idling will be out from the stock setting.
Any way, this is a good "discovery" posting

 

[chinozie]

Yup...
that's why we need to read the article based on the link given above...
need to mark the original position and check the valve orientation before removal...