I tried leaning out the OpLp A/F vs Temp table a few steps to correct a very rich condition during warm up. The adjustment did work and my truck ran great until it went into closed loop and warmed up to it's normal temp (180 degrees). I guess the knock sensor went crazy and my timing seriously degraded. I richened up the A/F for 64 degrees and above in the table as well as reduced the timing in the SA table. It eliminated the knock retard but it feels like it's lean at around 1600RPM and higher.

Does the OpLp A/F vs Temp table affect the tuning in closed loop too? Is this table the primary component of "open loop tuning"?

I would have done some datalogging right after this happened but my laptop puked. Your inputs are sincerely appreciated.

Mike
(7747 ECM using Moates DIY Prom hardware)

 

The OpLp A/F vs Temp table is only used in open loop. Once the ECM goes closed loop the AFR is commanded to be 14.7:1, and held there via the O2 sensor feedback set points. Note the 14.7:1 value is a calibration term and can be changed. Which doesn't matter because it is the O2 feedback that defines the actual AFR that the engine fueling is held to.

RBob.

 

Thanks for the input RBob. That's what I originally thought too but I swear that adjusting the OpLp A/F vs Temp table affected my VE table in closed loop. I fixed my laptop so I'll see what happened. I guess this is all part of learning the system...