1JZ Idle Weird,Please Help!

[GT500]

Hi guys,

My 1JZGTE Manual (JZA70) idles weirdly just recently after I had a very slight knock at the front.

Whenever I start my car now,the engine starts to idle from 1000rpm and jump straight to 3000rpm,down to 1000rpm and rise to 3000rpm for over and over again.The idle doesn't sounds rough,but it is just not right as the car should idle around 700~900rpm.

After a short while it will idle as usual,seems like the problems gone after the engine is in certain tempreture (drive for a short distance)

Some says ECU..TPS..Idle Valve...

What could be the problem guys?I really need to know since I need to travel with this car within this week.

Thanks.

 

[te72]

Heh, my car did that for a bit. Your ISCV is likely shot/stuck, or improperly wired. Here's a test for ya: unplug your iscv and have someone start the car. As soon as you start it, plug it back in. If I remember correctly, this should return you to a normal idle... Been damn near a year now since I've had to do that, so don't quote me on this one. I believe what fixed my problem was cracking the throttle with the set screw on the throttle bracket. All I know is that my car doesn't do that anymore and my iscv's plugged in like normal.

Really is unfortunate that our iscv's are a sealed unit, if it were a 7m or many other motors they can be taken apart and cleaned out... only so much you can do to help a sealed one.