Closed loop, O2 manipulation problem.
I originally purchased the UDR FTC.
This seemed to work fine with keeping the O2 target rich while still in closed loop.
I changed my piggyback to the AEM F/IC 8 which has built in O2 manipulation. The directions are vague, but they suggest installing a 1K ohm resistor inline with the O2 signal wire that the AEM intercepts. The resistor is in between the AEM and the stock ECU. The resistor is there so the AEM is able to manipulate the O2 voltage signal.
Basically in closed loop, the ECU wants to be at 14.7 AFR. Well if you are between 1-5psi and part throttle that is bad and the motor will knock.
So by using the O2 table you can input xx voltage to fool the ECU into thinking the engine is running lean so it will add fuel.
Well I've tried every resistor from 700ohm to 10k ohm (which was recommended by another Tacoma turbo thread somewhere I believe)
The problem is no matter what voltage I input to trick the ECU, the ECU dumps way too much fuel and I'm way too rich. It's like an on/off switch. It is so bad that I still have the URD FTC that I'm solely using for the O2 manipulation feature which works ok, but not perfectly.
Does anyone have experience with the AEM unit or any other piggyback unit with O2 manipulation? Not many threads on the subject