Probably an easy Q here but I'd like to get his clarified.
I've got the impression from many people that our cars go into Open loop while at WOT, or atleast on LS1 cars. I was scanning a '94 LT1 car using Datamaster and it stayed in closed loop even at WOT. The only difference was PE mode was active. Do LT1 cars stay in Closed loop at WOT but use the WOT enrichment tables to just add fuel on top? Or is Datamaster not showing me the right thing?

 

The "flag" that the scanner reports means "closed loop enabled" = all the conditions for closed loop have been met. It doesn't mean its accepting feedback from the O2 sensors at WOT (PE mode).

Its confusing because of the GM nomenclature..... "open loop" is basically cold start, "closed loop" is everything after open loop, and when you exceed the thresholds and need an enriched mixture for maximum power and torque, GM chooses to call it "power enrichment mode", even though it functions similar to "open loop".... just at a richer target A/F ratio. So your 94 is not using the feedback at WOT to alter the fuel calculations..... so its running equivalent to "open loop".... GM just doesn't call it that. And they keep the flag set for "closed loop enabled" to indicate the PCM is capable of operating in closed loop.

Confusing......

 

Thanks you very much, I'm UNCONFUSED !!!