06 Lexus IS350

unitedvisionary's picture
Submitted by unitedvisionary(5)18 October, 2008 - 07:49

Has anyone actually tried it on this car? I have the HAFC installed and Optimizer installed. Tried playing with the resistors with the decades box. Will work for some minutes, then tunes itself back. AFRs.

How do i fix this?

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mpgmike
mpgmike4 years 27 weeks ago

Re: 06 Lexus IS350

You're not using the O2ptomizer's O2 circuit on the AFRs are you? You should have between 17 and 18 ohms of resistance in the signal (high) side circuit to trim the AFRs. What are your fuel trims? They need to keep between 2 and 5% positive. If they are out of that spec, more MAF will bring them more positive and more resistance in the AFRs will bring it more negative. Did you tune the IAT for maximum power (ignition timing)?

You might have to add 1-2 ohms of resistance to the down-stream O2 "heater" circuit to raise the ECU's cat temp readings to keep them from dumping more fuel. That vehicle is typically an easy home run.

Mike

jeff_ronalds
jeff_ronalds1 year 38 weeks ago

Re:06 Lexus IS350

My friend do that on his Lexus few months ago. He actually installed few additional lexus parts for the conversion before he make another tuning. I can't remember how he fixed that but I will let you know when I ask him. Good luck.