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1jz-gte idle missfire / hunt

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I'm working on a 1jz-gte with a precision 6262, sard 650cc injectors, aem map sensor, AEM v2 Honda box. everything else is oem sensor ect.. so when I first got the car fired up, I got it to idle perfect. then a week later it started missing/hunting at idle, the afr's will jump from 14-16afr just back and forth same with the idle speed. the only way to get this stop is add fuel and make it idle at 12afr or richer. ive tested every sensor, replaced the intake manifold gasket, ive deleted the ICV, checked timing both electric and mechanical. it has good vacuum and compression I cannot figure this out. does anyone have any other ideas of what could be causing this idle issue?

Can you isolate which cylinder is playing up? I.e unplug each injector at a time and see which one makes the smallest change. This might help you know where to focus on.

AFR jumping up and down sounds like it could be a cylinder coming in and out of life and pumping out oxygen causing the lean mixture you're seeing. Possible injector issue, or coil?

In the ecu does it show any strange movement in other readings like MAP or TP or RPM while it is playing up?

Also was anything changed around the time it started playing up which could of caused the issue?

I've had the injectors cleaned/tested and swapped the coil packs with known good ones. No I haven't tried to isolate which cylinder is acting up, maybe I should do that and then check and see if it's a injector driver or coil driver inside the AEM?

All the sensors are reading good I believe, how much should the rpm reading fluctuate in the aem program while at a steady idle, like 20-30rpm?

Nothing was changed on the car while it started acting up it was being driven when it started acting up.

Thanks for the reply

Idle would normally move around 20-30rpm depending on motor. Something with bigger cams etc would be more like 40-50

I would try isolate a cylinder and go from there. If it all of a sudden started playing up while driving then something must of changed/failed.

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