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Problem tuning idle

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I have a US spec 2jzgte and a infinity 6. I'm trying to tune my idle but I'm having a problem with hunting. Any help would be greatly appreciated.

Getting an engine to idle well in all conditions can be tricky, especially on modified engines. The following advice assumes you are still using an idle air control valve, the stock idle air control valve for 2JZ engines is attached to the intake manifold.

For idle tuning, a good place to start is disable feedback completely by setting the min/max idle FB limits to zero. The idle base RPM and idle base tables should be tuned well enough that the engine idles without stalling, and it's OK if the idle is a little high when feedback is disabled. Then, you know that any remaining instability is not because of changes in the idle valve position, so you can focus on getting fuel and ignition dialed in around idle. If the car has a tame enough clutch, leaving the throttle at zero but dragging the clutch slowly to start rolling is a good way to introduce some load. If the VE Table isn't dialed correctly, this will cause the engine to run lean and try to stall... fix the VETable and the engine will be less likely to stall when the load increases. When you feel the fuel and ignition and idle base settings are working better, try turning the idle feedback on again to make sure the idle feedback is doing a good job of responding to changing load conditions but not overshooting or causing instability.

Hope that helps,

SB

Thanks a lot! I think this will help me. I will give it a shot and get back to you. I have a clear understanding of everything. I just think my excitement gets in the way of things lol

The 2J will idle quite happily without a stepper, provided fully warmed up, by implementing a idle ignition advance curve...the lower the rpm..the more advance timing. Elaborate (play) with it and you will quickly get the feel of what advance curve your 2J likes best. Once you are near, adjust mixture as well...but that is merely a correction factor.