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Discussion Starter #1
So when the ECU detects open loop on our cars what all is disabled? I know of EGR but what else? Will the AC compressor clutch deactivate as well? What else?
 

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Open loop is once the computer detects that the engine has warmed up it starts using all the sensors (engine temp, oil pressure, coolant temp)to run the car rather then pre programmed algorithms
 

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Open loop is once the computer detects that the engine has warmed up it starts using all the sensors (engine temp, oil pressure, coolant temp)to run the car rather then pre programmed algorithms
Umm. Yes/No. Open Loop vs. Closed loop. For ECU. Open loop refers to when the ECU no longer uses input from the o2 sensors to calculate fuel delivery. I.E. your Air/Fuel ratio will no longer be for fuel economy (you will run richer). There is another sensor (WOT (wide open throttle) that is detected, that disengages things like the AC clutch (if AC is enabled). It may just be a 'terms' difference. But if you tell a tuner you want to adjust "open loop" you may not get what your wanting. [eek]
 

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Just to let you know my ST disables the AC at WOT. But there are some 2.0's that I've datalogged that didn't disengage the AC at WOT.
 

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Discussion Starter #9
Interesting. I haven't done any datalogging for seeing if mine truly turns off at WOT but it sure feels like it doesn't. Although talking to Randy he says every car is different in the amount of time it takes to detect WOT and transfer to open loop. Some cars are instant whereas others may take a second or two.
 

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Discussion Starter #11
Are these things turned on an off in the making of the tune or is it something the user can do through the use of the XCAL in the option menu? I would go out and look myself but I am away from my house..
 
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