2JZ-GE High Idle

[ark_112]

Hi Guys,

Two days ago my car started idling at around between 1000 and 1300 rpm once it is warm. I have taken the ISCV off, check that is worked (goes in and out) and cleaned it. This made a slight difference as the car only idles around 1000 rpm now, however if I manually wind the ISCV out a little bit before putting it back in I can get it to idle at the right rpm but once I turn it off and start again it is back to the high rpm (guessing that it gets wound back as far as it can go when its off).

I have also checked that my throttle is closed properly and it appears to be. I have also checked that all vacuum lines are plugged in and I will check if they are leaking.

The last thing I tried was resetting my ecu (pulling EFI 1 and 2 for 15min), which didn’t seem to make any difference.

Any other ideas?

[Hiro]

Is there something like a cold-idle, air-con or p/s idle-up valve that is stuck open, so it's always telling the ECU to up the idle on the ISCV? Could be that the ISCV is perfectly fine, but something that controls it is dodgy/faulty.

[ark_112]

Thanks I'll check all that out. I hope its not my ISCV thats stuffed as I just got an estimate price of $2027+gst from the toyota dealer I get my parts from in NZ :O

[DrNick]

Sounds like you may have a bit of an air leak somewhere after the throttle plate.. It has happened to me in the past as the gaskets are metal and often dont seal as well as they should when they have been off a couple of times. Try making sure all the TB and Y pipe bolts are tightened up properly.

[ark_112]

DrNick: i have had Y pipe off once, but that was a long time ago. I do have a spare gasket for it so I might try that.

[neal]

NZ$2027 for a iscv valve are you sure. Thats awefully lot.

[ark_112]

Thats what Rory at Rutherford & Bond Toyota told me, he said they had never had them before but that was the estimate list price from japan.

I have been playing around a bit more with it tonight and notice that once the car is warm if I turn it off, then back on it will start then drop to about 750 rpm for about a second then raise to and stay at 1000rpm.

How does the engine sense for a cold start, does it use the termostat thus could my thermostat be stuffed and reporting wrong and the einge still thinks it's not up to normal temp?

[progkamol]

My 2JZ GTE idles at around 1200rpm ... but thats on a heavily moded car with LT10 ... it been tuned over and over again and yet it still idles at 1200rpm ... It has been like that for almost 2 years now tihout a problem ... I tried to play around with the LT10 hand controller to try lower the idle and that results in the engine stalls so i left it to idle at 1200rpm

[wa5]

Not trying to hijack the thread, but I was talking to a older bloke today in Newcastle with a similar problem with a Naturally Aspirated JZA80.

Anybody in Newcastle know where I could point this guy for some advice, repairs...?

[ecko]

check coolant maybe? its normally controlled by coolant temp so check theres no air in the system that might be causing it

[ark_112]

Thanks for the replies guys, I haven't fixed it yet and have had a look at most of the suggestions. I tihnk I will just try to live with it for now as I want to buy a 2jz-gte in the near future anyway

[ark_112]

The problem has now fixed itself lol I noticed that it was idling normally yesterday on my way home form work.

[<cozzy>]

gday mate....

all fixed? iv never had a high idle problem only a low idle problem....
i just turn car off then start it again and its fixed,
yeah only thing i could think of would be vacuum hose off or leaking gasket...
maybe dodgy batch of fuel or injector problem?
oh and i'l buy your 2jz-ge off ya when you get turbo engine for it lol

cheers

[ark_112]

Well I brought a 2JZ-GTE last week which is gonna take a month and a bit to get here then I will have to chase up a few parts, Ill let you know when its for sale.

[<cozzy>]

allright sounds the go thanks mate

[Alchemist]

When you refit the ISCV one of the screws can be loosened and the ISCV can be moved around marginally, you'll find you can actually make some 100rpm adjustments just by sliding it around and experimenting, had to do this to get my idle down after I changed my spark plugs.

Mine cold starts to about 1200-1300 drops back to around 900 when warmish and them usually down to around 800 idle.