jrdnclrk Posted March 6 Report Share Posted March 6 Hello again guys. I'm having some issues with my vvti settings on my is300 itb 2jzge. The issue appears to be with the settings from what i can tell. With the vvti turned off the car performs fine under all throttle conditions except the intake cam isn't varying and stays at 0*. Now when i have the 2jz vvti setting turned on using my tps as a load axis. with mildly aggressive settings in the mid range the car bucks like a timing error under transient throttle conditions. Now if i set all the vvti targets to 0* this issue still happens. which has led me to believe the settings for 2jzgte vvti (3 cam teeth) and 1jzgte vvti (2 cam teeth) are somehow not applicable to 2jzge vvti. i have tried the calibration setting in the vvti set up cam angle test selection as well. no effect. I've also tried datalogging this issue but nothing shows up on my logs as far as trigger errors or anything obvious. I'm currently driving with the vvti setting off till i can get this issue sorted. If i have any incorrect info here please let me know. 2jz itb vvti issue.pclx Quote Link to comment Share on other sites More sharing options...
Vaughan Posted March 6 Report Share Posted March 6 Going to need a PC Log of a drive in which it does the bucking and a copy of the tune used for that logged drive Quote Link to comment Share on other sites More sharing options...
jrdnclrk Posted March 7 Author Report Share Posted March 7 i logged this tonight. you can see the bucking in the rpm and tps signals as acceleration goes up. 2jz itb vvti issue.pclxissue with vvti.llgx Quote Link to comment Share on other sites More sharing options...
Vaughan Posted March 7 Report Share Posted March 7 Looks like the problem is that it is going lean because the cam angle is making it flow more air than it does when the cam is in it's rest position. Try adding more fuel at that point in the fuel table. Quote Link to comment Share on other sites More sharing options...
Adamw Posted March 7 Report Share Posted March 7 I think your PID on the cam control might be a bit aggressive too, there is a bit of oscillation in a couple of areas. In the VVT settings, change the PID setting to custom and reduce the proportional gain to about 3.0, and the base duty to about 42%, this will likely settle the oscillation down. 19 hours ago, jrdnclrk said: which has led me to believe the settings for 2jzgte vvti (3 cam teeth) and 1jzgte vvti (2 cam teeth) are somehow not applicable to 2jzge vvti. Although it would work fine with either tooth count since G4X populates the tooth count and tooth offsets tables during the cal process anyway, I thought I would correct this statement so it doesnt confuse others in future. The 1JZ and 2JZ VVTi cam pattern is identical, 3 evenly spaced teeth on both. Quote Link to comment Share on other sites More sharing options...
jrdnclrk Posted March 7 Author Report Share Posted March 7 updated with no changes. I've also tried setting all vvti targets to 0* and the problem stays. Also thank you for the correction on cam teeth. 2jz itb updated vvti to custom.pclx bucking with updated vvti settings.llgx vvti targets set to 0.llgx Quote Link to comment Share on other sites More sharing options...
Vaughan Posted March 7 Report Share Posted March 7 You didn't add any fuel to where it was missing, your bucking issues are because you are lean, tune your fuel table to suit your vvt targets. As a side note lambda over analog is usually not the most accurate so if your lambda controller supports CAN I would highly recommend using CAN instead of analog. I've attached a screenshot showing noise in your lambda signal that lines up with battery voltage. Quote Link to comment Share on other sites More sharing options...
jrdnclrk Posted March 7 Author Report Share Posted March 7 4 minutes ago, Vaughan said: You didn't add any fuel to where it was missing, your bucking issues are because you are lean, tune your fuel table to suit your vvt targets. As a side note lambda over analog is usually not the most accurate so if your lambda controller supports CAN I would highly recommend using CAN instead of analog. I've attached a screenshot showing noise in your lambda signal that lines up with battery voltage. Noted. I also would like to reiterate that the bucking problem still happens when the targets are set to 0 degrees Quote Link to comment Share on other sites More sharing options...
Adamw Posted March 9 Report Share Posted March 9 Can you give us a log of it behaving "normally" with the VVT off. The way it goes instantly lean at ~2700 looks more like a misfire rather than tune related. The increase in Inj PW through that range appears to be proportional to TPS and the fuel table value so there shouldn't be a sudden change in AFR. I dont see any relationship to vvt in this log. TTP 1 Quote Link to comment Share on other sites More sharing options...
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