Toyota idle valve control

[mr2.3sge]

Hi there,

I'm runing a 3SGE VVTi from 98 which have a 3wire idle valve (12V, idle input, ground) I think that is a PWM valve control.

I'm tring to do a fine tune of a closed loop idle control. Does anyone have any idea what are the settings that I shoudl put? Min and Max duty-cycle? PID gains? etc...??

Thanks for your help

[muythaibxr]

If this is anything like the 20v 4age 3-wire valve, you have the pinout wrong. You want 12v in the middle, 1 "open" pin and 1 "close" pin. So 2 wires run to the MS and you put it in 3-wire mode.

[ekam99]

40% and 100% for min/max dc, but check for your valve specifically using a test mode.
Make sure you use 3 wire option. It would work with 2-wire option, but you would not be able to set rpm low than some level.
Stock ecu drives valve on ~ 250 Hz. Mine works well on 306 Hz. (As mentioned by the previous post, pins on the valve are: +12, open and close (rso/rsc pins on the ecu)).
Use an initial table(dc vs CLT), not previous value; sensitivity~ 3300
Dashpot adder tune for yourself, as well as initial table, cranking dc etc.

These works fine on my 3 gen 3sgte.

[muythaibxr]

Don't use DC vs CLT, do it vs MAT. CLT is already factored in by the target curve.

[mr2.3sge]

Here it is a idle valve diagram (idle input, +12V, ground).

Yes my idle valve works with 250Hz from OEM ECU but I set it to 306Hz too.

I'll try it today with these values.

Thank you guys, I'll post the feedback soon

[muythaibxr]

looks like the same valve to me, but on the 20v 4age they don't run it that way.

[ekam99]

If you are able to set the idle at low level leave the wiring as is.(Again, you can check this in the test-mode lowering a dc) If not, route the brown wire from the ground to pwm out of ms and switch to 3-wire mode.
It all depends on the size of the valve and initial (not-powered) position.

[mr2.3sge]

I run the idle test mode from 0% to 95% and the idle didn't change (running 90ºC-100ºC).

If you are able to set the idle at low level leave the wiring as is.(Again, you can check this in the test-mode lowering a dc) If not, route the brown wire from the ground to pwm out of ms and switch to 3-wire mode.
It all depends on the size of the valve and initial (not-powered) position.

I'm using the OEM engine wiring and I'm always changing the ECU when I want to drive my car. I still cannot drive my car with MS3pro module ECU.

I connected this idle valve wire to idle pwm output.

Here it is my msq file.

[pit_celica]

Verify that the IAC valve itself is working. Unplug the IAC connector and make sure that the RPM goes up. Verify that you actually have 12V at the center pin. Verify that the RSC coil (pin #3) is connected to ground. On my setup, my settings are :

Algorith : PWM closed-loop
Valve mode : normal : 0% = OFF
3-wire mode : OFF
Frequency : 613hz

I never tested different frequency. I found a user using this frequency and I use it as is.

You should use a voltmeter to verify the voltage at idle pin when the PWM is varying.

Sam

[mr2.3sge]

Verify that the IAC valve itself is working. Unplug the IAC connector and make sure that the RPM goes up. Verify that you actually have 12V at the center pin. Verify that the RSC coil (pin #3) is connected to ground. On my setup, my settings are :

Algorith : PWM closed-loop
Valve mode : normal : 0% = OFF
3-wire mode : OFF
Frequency : 613hz

I never tested different frequency. I found a user using this frequency and I use it as is.

You should use a voltmeter to verify the voltage at idle pin when the PWM is varying.

Sam

Hi Sam,
Wiring checked and it is correct (pin#1 to PWM idle, pin#2 to 12V and pin#3 to ground). Voltage at 40%duty is around 5.20V and at 89%duty is 5.60V.
The idle didn't change with unplugged valve.

I made a complete cold start datalog. I don't know why MS is putting more fuel (PW) when the engine is cold because I deleted the ASE, WUE and set the Priming pulse to 2. My engine is swimming on fuel at cold start! The idle is always changing and it is hard to have the engine running without some TPS%.

I cannot put the datalog here because it has 9,5Mb :/ (didn't know that was a max, allowed size for it)

[pit_celica]

You can zip the log file to reduce his size. You could also use a service like dropbox and post a link.

Is the idle valve working correctly when used on the sotck ECU? If you unplug the idle valve while the engine is running on the stock ECU, does the RPM rise?

Sam

[mr2.3sge]

You can zip the log file to reduce his size. You could also use a service like dropbox and post a link.

Is the idle valve working correctly when used on the sotck ECU? If you unplug the idle valve while the engine is running on the stock ECU, does the RPM rise?

Sam

Hi,
Yes the valve is working perfectly with oem ECU and the idle rises when I unplug the valve.
I tried to drive the valve with 613Hz too and it has the same actitude.

The problem at cold start was solved. Cranking RPM was too high (700rpm). I put this value to 400rpm and seems much better now.
Its time to get a good idle...

I checked the frequency and it runs at 250Hz.

Part# 22270-74370

Came on:
Japan TOYOTA MR2
Japan TOYOTA CELICA
Japan TOYOTA CALDINA
Japan TOYOTA RAV4

Only on 3SGE VVTi (RedTop and GreyTop)

(toyodiy information)