Closed Loop for Dummies?

[NewV]

If I want to go back to closed loop does that mean that the engine will always attempt to maintain 14.63 AFR or is there a way to command it like in open loop B3605?

[SSpdDmon]

If I want to go back to closed loop does that mean that the engine will always attempt to maintain 14.63 AFR or is there a way to command it like in open loop B3605?

It will try to maintain the Stoich ratio set in B3601 IIRC. Keep in mind the NBO2 sensors are only good around a 14.6 AFR. Unless the engine coolant temp is below the values in B4205 (closed loop temp enable), you should be in closed loop. B3605 (open loop fueling) is for when the engine is warming up after startup or while in PE (PCM will use richer value between B3605 and B3618 +/- any adders). For the most part, this table isn't used that much while in closed loop - just during warm up and PE like mentioned above.

You can (with a custom OS) run semi-closed loop. The other option that I would suggest is to adjust the PE enablers to come on sooner if you don't want to run a 14.63 AFR at moderately higher engine loads.

[Tordne]

Custom OS3 with Semi-Open Loop is a good option.