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.

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

Thanks.

 

[bLACKjAC]

call Simon 012-2268972, my mechanic, he is good for old version car, my 2jz has been done well by him.

 

[arepeace]

my 1jz hv the same problem oso
but with aircon on
no aircon on,the idle back to normal

 

[renxun]

cabut the socket plug at idling control valve and see if it drops low to 500rpm ..... if it drop and idles there... tat means your valve have problem.... probably need some cleaning inside or its completely spoilt

 

[jo-e34]

pm...me for location if u guyz dont mind travelling down to seremban for a cure.....

 

[Veloc]

That is one of the almost definite symptoms of a vacuum leak. Check all vacuum tubing and see whether there are any disconnected, cracked, broken, loose vacuum hose connected to the vacuum manifold i.e Map sensor tube, blow-by gas tube.

Also, check the pcv valve at the blow-by gas tube as old engines tend to have a blown pcv valve.

 

[1JZtezza]

check if blow-bye gases have gone past the one-way valve into the manifold and clogged up/melted the map sensor.If so u got to clean up the throttle body,O2 sensors etc.If still same idling problem change the ECU!