Closed versus Open Loop
#1
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Closed versus Open Loop
When and what cause or allow the PCM to begin operating in open loop versus closed loop mode?
I searched but never found a definitive anwser.
Thanks
Mike
I searched but never found a definitive anwser.
Thanks
Mike
#2
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Re: Closed versus Open Loop
LS1 always start in open loop (air fuel ratio table in edit), even if the car is warm. This gives the o2 sensors time to warm up. It then switches to closed loop for idle and cruise. For WOT it switches back to open loop (PE tables in edit). You can change the closed loop enable temperature in edit to change how long it stays in open loop. Or if you don't want to run o2 sensors you can leave the car in open loop full time.
Gary
Gary
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Re: Closed versus Open Loop
There are a host of sensors that allow a car to go from open loop to closed loop. The O2 sensor is one of the more important ones, along with the ECT. In any case, you get better power and fuel economy in closed loop. Closed loop just means everything is reporting into the PCM, and the car is warmed up.