Idle Control with the 1jz

[Mindless]

Ive got a MicroTech LTX- 12 standalone ECU in my 1jz-gte ma61.
ive been reading up and the ecu i have doesnt have any sort of cold start or idle control options with it..

for me, my car wont start up unless i rev it to a decent rpm(1000-1500) for a few minutes for it to idle since it just wont idle itself, and needs my help although i have heard that the factory ecu would take it to 2000 then it would drop back down to the normal idle rpm..

ive been reading around that a few people have done different things to get around this, they have kept the OEM ecu for the idle control and had an aftermarket ecu fitted for the other aspects.
another is to get an ecu with the idle control option..

so i was wondering if anyone has had similar problems to me and what they have done to get around it..

[YLD-16L]

At the moment I'm setting up a simple cold start setup on a 1JZ running a Microtech similar to yours but won't be using the Microtech for the cold start control as we've already used up all the auxillaries for other things.

Just going to use a solenoid to bypass the throttle for cold start and a thermatic switch temp sensor to control when it opens and closes.

Other than that I don't expect to have any other idling issues with the Microtech as all the other cars have been fine with them at operating temp.

[Mos]

Can't you just use a ford 2 wire idle speed control valve and a PWM output for idle control? (assuming you have outputs left).
Mos.

[The Real Roadrunner]

do you need idle control or do you just want a decent cold start?

a rotary air valve off a VL (and many others) can be plumbed in by connecting 2 air hoses and an ign on 12v plus an earth.

or as moss suggested an XF pwm idle valve will do the job nicely if you have a spare pwm output.

cheers
linden

[Mindless]

I think that i would need a good coldstart, what iam after is. on start up for it to shift between 1500-2000 rpm then when it has warmed up, it will come back down to idle around 900, at the moment it isnt doing this..anyhow when it does warm up, it runs fine and idle's well.

When i pull up to lights and the thermo fans come on to cool down everything that is where it dies and drops to 400 rpm or so to sometimes stalling.. so yes i would need both a decent cold start and good idle, iam pretty sure that i would have some outputs available since i dont have too much aftermarket stuff connected up..

i think this is easier to understand

[Mos]

Punctuation please
Mos.

[Mindless]

yeah i think you'll find that it makes a lot more sense

[chris davey]

your ecu only has one aux output. If you aren't using this then you can setup a ford valve as suggested above and make it open at whatever temp you want. Actually, now I think of it I am not sure if the microtech does this? Don't have my book handy May want to go down the same path as YLD as this means you can use your aux output for something else (like nitrous )

[CrUZida]

Generally speaking people with LT12's and 6 cyl engines run all 6 injector and ignition outputs, so they don't have any left for idle control.

Just set the warm idle to about 800-850 by opening the throttle plate, and hook up an idle solenoid that is controlled by coolant temp like others have suggested.

You cannot run a PWM valve unless you are running wasted spark ignition or semi batch fire injection.

[Mindless]

I checked and i dont have any outputs left..
i might take it over to sas and try the solenoid temp sensor
atleast they know what they are doing compared to if i started stuffing around..
thanks for all the replies they have been very helpful