'02 IS300 with 1jzgte VVTI Fuel Trims messing with me
03-22-18, 05:29 AM
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'02 IS300 with 1jzgte VVTI Fuel Trims messing with me
Hi all,
I have a manual 02 IS300 that I have just put a 1jzgte VVTI in. I'm using the stock 2jzge loom and ecu and controlling fuel with an Apexi AFC Neo.
I am having constant issues with the fuel trims going to extremes (both - and +) which obviously changes the AFRs.
When I reset the ECU, the trims go back to zero and the car runs great. But after a day or 2 of driving, the trims either go to -29 or +29 and this drastically changes the tuning that is being done via the AFC Neo. I can't leave the trims at that level and re-adjust the AFC because the trims are not constant (cruising vs WOT).
I only have 1 of the stock o2 sensors connected, and am thinking of splicing the 2 pre-cat sensors into the 1 remaining o2 sensor so that the ECU at least reads something. I am fine with a CEL being on all the time for the other o2 sensors being removed, but just trying to get the fuel trim levels to remain consistent.
Anyone have any ideas on how to achieve this? I have been googling for days but can't really find much info.
I have a manual 02 IS300 that I have just put a 1jzgte VVTI in. I'm using the stock 2jzge loom and ecu and controlling fuel with an Apexi AFC Neo.
I am having constant issues with the fuel trims going to extremes (both - and +) which obviously changes the AFRs.
When I reset the ECU, the trims go back to zero and the car runs great. But after a day or 2 of driving, the trims either go to -29 or +29 and this drastically changes the tuning that is being done via the AFC Neo. I can't leave the trims at that level and re-adjust the AFC because the trims are not constant (cruising vs WOT).
I only have 1 of the stock o2 sensors connected, and am thinking of splicing the 2 pre-cat sensors into the 1 remaining o2 sensor so that the ECU at least reads something. I am fine with a CEL being on all the time for the other o2 sensors being removed, but just trying to get the fuel trim levels to remain consistent.
Anyone have any ideas on how to achieve this? I have been googling for days but can't really find much info.
03-23-18, 10:10 AM
#2
You need a standalone ECU. That's the only thing that will stop this from happening.
You cannot use the stock 2JZ-GE ECU with a turbo kit, let alone a GTE motor, because it will constantly try to alter fuel and timing to its preprogrammed stock motor fuel map. In your case it makes driving your VVTI GTE motor dangerous because you can lean out and blow it up.
If you google "AFC Neo IS300" you will find a lot of threads on my.IS that say that the Apexi controllers are useless on the IS300 because the ECU cancels out the tunes. I'm surprised in all your searching you didn't discover that.
You cannot use the stock 2JZ-GE ECU with a turbo kit, let alone a GTE motor, because it will constantly try to alter fuel and timing to its preprogrammed stock motor fuel map. In your case it makes driving your VVTI GTE motor dangerous because you can lean out and blow it up.
If you google "AFC Neo IS300" you will find a lot of threads on my.IS that say that the Apexi controllers are useless on the IS300 because the ECU cancels out the tunes. I'm surprised in all your searching you didn't discover that.
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paradise8
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