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**Gregski** · 11-17-2019, 02:02 PM

Vehicle Running - Closed Loop

lets take a deeper dive and see what exactly caused that switch from Open Loop to Closed Loop

We know all of our configuration settings come from the VCM Editor so we fire it up and go to Engine \ Fuel \ Oxygen Sensors and look under the Closed Loop Enable heading where we find the ECT vs. IAT table (highlighted in pink for easier spotability that's all)

We put our mouse over it, and glance at the bottom of the screen where we find the Context Clues, which read: This table sets the coolant temperature required to enable Closed Loop in relation to inlet air temperature (IAT).

We open up that little guy, and it's not really a table as it is a list, but so be it. We quickly and easily see that once the ECT (Engine Coolant Temp) hits 131 (the big green bar) and our Intake Air Temp is above at least 50* we will turn on Closed Loop. Cool beans, so things are working as they should and now we know why.

Don't take this for granted, someday you may be troubleshooting an issue caused by your PCM never entering Closed Loop mode, so just keep that in mind please.

11-17-2019, 02:02 PM	#216
Gregski Post Whore Join Date: Aug 2014 Location: Sacramento, CA Posts: 10,803	Re: HP Tuners Tutorials - Chapter 1 - Logging Vehicle Running - Closed Loop lets take a deeper dive and see what exactly caused that switch from Open Loop to Closed Loop We know all of our configuration settings come from the VCM Editor so we fire it up and go to Engine \ Fuel \ Oxygen Sensors and look under the Closed Loop Enable heading where we find the ECT vs. IAT table (highlighted in pink for easier spotability that's all) We put our mouse over it, and glance at the bottom of the screen where we find the Context Clues, which read: This table sets the coolant temperature required to enable Closed Loop in relation to inlet air temperature (IAT). We open up that little guy, and it's not really a table as it is a list, but so be it. We quickly and easily see that once the ECT (Engine Coolant Temp) hits 131 (the big green bar) and our Intake Air Temp is above at least 50* we will turn on Closed Loop. Cool beans, so things are working as they should and now we know why. Don't take this for granted, someday you may be troubleshooting an issue caused by your PCM never entering Closed Loop mode, so just keep that in mind please. Attached Images Last edited by Gregski; 11-29-2019 at 11:22 PM.