Stock ECU Fuel Trims Changed Suddenly! WTF?
 

Here's what I have going on:
eManage Ultimate with Celica GTS Injectors set up at 270cc. Dyno tuned nicely. My Long-term fuel trims have been about +25%. Stock ECU will not throw lean or rich codes as long as fuel trims are within +/-35%. All of a sudden my long term fuel trims have jumped up to 45% and now throwing a system too lean code. Car runs great, especially in open loop while boosting. But at idle it's super lean and thus forcing the stock ecu to add way more fuel than before.

I live in Chicago and the weather has changed greatly in the last week....could that have such an effect on the ecu that it uses a different fuel map? I'm stumped.

Vacuum leak!

That would do it.

Yep! And to the OP, please get your adaptives in closer. They should ideally be within +/- 5%

LTFT's are within +/-8%

Running like a champ now. Wish that Greddy gave me the right info before i dropped loot on 440cc injectors that EMU can't control without additional Greddy electronics!