3S-GTE Idle problem

[Ramsey]

Hey all,

My idle on my 3S-GTE starts to drop 300 RPM from about 880RPM when I turn my headlight on and some times when I get on the brake whilst sitting at the traffic lights. Could this be a alternator and battery problem or something different?

[jonathan yee]

Std ecu? Does it idle up on cold start, or when turning steering or with AC on?

[jondee86]

My idle on my 3S-GTE starts to drop 300 RPM from about 880RPM when I turn my headlight on and some times when I get on the brake whilst sitting at the traffic lights.

Typically, there will be some kind of electric idle-up solenoid valve, that opens when extra electrical load is applied to the engine. This will let air into the inlet manifold to raise the idle (or stop the idle from falling). Check that the valve is still functioning by removing the plug and applying 12V to the pins on the valve. The idle should go up with power on, and drop with no power.

Cheers... jondee86

[Ramsey]

Std ecu? Does it idle up on cold start, or when turning steering or with AC on?

Aftermarket ECU, It's a Microtech LTX8. On cold start I have to warm It up to about 60 degrees or idle drops and starts dieing and sometimes would stall. Does'nt do It when I turn the wheel and It has no Aircon haha, needed room for the Intercooler.

[Ramsey]

Typically, there will be some kind of electric idle-up solenoid valve, that opens when extra electrical load is applied to the engine. This will let air into the inlet manifold to raise the idle (or stop the idle from falling). Check that the valve is still functioning by removing the plug and applying 12V to the pins on the valve. The idle should go up with power on, and drop with no power.

Cheers... jondee86

Cheers for that Jondee86, I'll give that a go when I got time on my busy schedule.

[jonathan yee]

Sounds like you don't have the iscv operating via the microtech, and it's hasn't got sufficient setup for cold idle up.

Has it been tuned/fitted recently?

[Ramsey]

Sounds like you don't have the iscv operating via the microtech, and it's hasn't got sufficient setup for cold idle up.

Has it been tuned/fitted recently?

I got It tuned recently and the tuner said It doesnt have a cold start setup. Do you know If the ISCV can be ran through the Microtech or would I need to run wires to a switch and operate It manually somehow for cold starts?

Edit: Was Fitted before I bought the car.

[foamy]

Microtech's dont have any sort of cold start or idle up afaik

[jonathan yee]

They can if you have spare inputs.

[MWP]

Aftermarket ECU, It's a Microtech LTX8. On cold start I have to warm It up to about 60 degrees or idle drops and starts dieing and sometimes would stall. Does'nt do It when I turn the wheel and It has no Aircon haha, needed room for the Intercooler.

Well there is your problem... youve got a Microcrap
Microtech's (any of them) are just not up to the task of running a street driven engine properly.

Try to find 1-2k and replace it with something decent.
Trust me, it'll be the best thing you ever do for the car.

[MWP]

[weird duplicate]

[Ramsey]

Well there is your problem... youve got a Microcrap
Microtech's (any of them) are just not up to the task of running a street driven engine properly.

Try to find 1-2k and replace it with something decent.
Trust me, it'll be the best thing you ever do for the car.

It came with the car, I had no choice haha. I'll go look for a better one soon, what one would you reccomend?

Edit: Cheers for the info

[dnegative]

They can if you have spare inputs.

I thought they plain out couldn't run a ISCV and could only handle your shitty on-off AC idle up jobby if like you say, spare input/output

[dumbass]

Just hook up a valve that idles motor up
Then power it when lights are on or brakes or fans or whatever makes it drop idle
Run all the inputs thru a diode for each f them so u don't get back feed
It's very crude but not as crude as the microtech hehehehehe

[MWP]

I replaced the normal 3SGTE idle solenoid with a 2-wire PWM unit from a Falcon that the Microtech could control.
It worked ok'ish... but the Microcrap still couldnt handle all conditions properly. It would still stall at certain times unless i set the idle to >1000rpm (very annoying).