When I try to log fuel trims in Evoscan all I get is 0.0. I'm using Tephra. I do not get anything in any fuel trim including O2 Feedback.

I logged the voltage on Oxygen Sensor and Oxygen Sensor #2. Oxygen Sensor was always reading 0.9 and Oxygen Sensor #2 averaged around 0.6 and had a range of 0.4 to 0.8.

Anyone have any idea why no fuel trims are reading? I am not forcing open loop in the periphery bit by the way. I did notice I'm logging more airflow at idle than my Closed Loop - LT Trim Control is set to use at Low. I haven't even researched scaling yet but just wanted to make sure I could log fuel trims first.

I'm averaging over 60 airflow at idle and my trim settings are Low > Mid 56.25 and Mid > Low 43.75

I'm guessing my Low to Mid value should be higher than what I'm idling at?

 

Do you have different injectors? Youre super rich either way, causing an open loop condition.

 

I have ID 1300s. I just drove around and things were logging and trims adjusting. Cruising around I was bouncing around 14.7 AFR but at idle I must be open loop because I have no O2 feedback. Fuel trim mid is logging at idle, not low.

 

Whats your tps voltage at idle?

 

I figured out load was what was keeping me from going closed loop St idle. Load values for those RPMs were set to 10 in my tune.

 

That was going to be my second guess! Good deal. Glad you figured it out. She idle like a kitten?

 

Much more lope at idle than when forcing open loop and idling rich. I have S3 cams by the way. I'm having to up my scaling a lot but definitely making progress now. I was like 710 with ID 1300s and idle O2 feedback was pegged at - 25.0

 

Nice. S3s are fairly decent at a raised idle. If you were on gas, wow.... Id say thats a little off. If its on e85, which Im guessing you are, it should be around 800 with the provided latencies.

 

I ended up at 790 and staying +-2.5 fuel trim at idle. I'm messing with my VE Table now to dial in different cruising cells that the trims are not as good on.

Is using the VE table a reasonable way to dial in the areas where I'm getting bigger changes in fuel trims?

 

Multiply ways to skin a cat. The best way is to do it with the injectors.

Depending how you look at it, to an extent you can use VE to adjust trims.

+-2.5 is good. Id drive around and if your fuel trims are negative I would lower the latency by 3% across the board and then redo the global.... I thinks that the way it goes. Been a day or two since I did my injectors.

 

Here is a little something for you. Im sure you have this. Figure it was worth posting.

 

That's what I was looking at. That and a thread someone made on an Evo X forum. My problem is that I have no idea what my VE should be so at certain loads my trims would be good and they would be bad at other loads. I don't think I can properly scale the injectors if my VE table is messed up. Never would have thought about how that would affect scaling injectors.

 

If everything looks good at idle you prolly just need to change a few of the cells. Dont block tune. Block tuning on a SD map will only give you problems. Make sure it all blends together. Seems like youre almost there.

 

Thanks for the help

 

Any idea what sort of VE would be correct around idle cells with S3 cams? I'm obviously off because when I go open loop pulling out the car almost stalls it goes so lean.