Quote:
Originally Posted by Darrel Goheen
Thanks again Ed and to all of you. I really do appreciate all the help!
|
Darrel, you can set the minimum RPM for Closed Loop high enough to only function at WOT until you get your idle and part throttle. If your O2 sensor in in the collector, closed loop can make your car very rich. Big cams with a lot of overlap will pull clean air in the collector, tricking your ECU into "thinking" it is running extremely lean, it will really pour the fuel to it to correct that perceived lean condition.
The 2 step has a similar effect. Misfires from the rev limiter put oxygen in the exhaust, which looks lean to the wideband & ECU as well.
Mine shows over 15-1 sitting on the starting line, on the 2 step. If in Closed Loop there, it gets so rich it won't leave. My converter flashed to 6200, air/fuel doesn't clean up until 6500/6600. I think it would be making false corrections below that. So, I can't enable Closed Loop until 7000. My VE table has 500 RPM breakpoints. I have worked on my fueling until it never makes over a one percent correction in Closed Loop now.
Might see what David says about this, but it has worked for me.