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DFI 6.32 Low and High Closed Loop Speed (RPM) Question

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Old Oct 16, 2004 | 05:47 PM
  #1  
GroundPoundinZ's Avatar
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From: Illinois
DFI 6.32 Low and High Closed Loop Speed (RPM) Question

In The ECU Configuration menu there is a High CL speed and a Low CL speed sub menu that has different RPM values that you can input. I am somewhat confused and hoping someone can shed some light.

I will type exactly what my CALMAP User's Guide states in the book.

5.16.7 High CL Speed (RPM)
THis sets the engine speed that must be exceeded before switching from closed loop to open loop.

5.16.8 Low CL Speed (RPM)
Below this engine speed, the system will no longer operate in closed loop mode.

NOTE: these two rpm thresholds define the band of hysterisis where closed loop operation is allowed.

OK, my questions:
1. If I'm understanding this..... they are recommending that I idle in open loop all the time. Correct or incorrect?

2. Don't I want to be in cloed loop once the engine reaches operating temp regardless of RPM?

Sorry for the lengthy post but I wanted to give everyone as much info as I have. TIA.

P.S. I'm thinking the CL throttle limit (%) may have something to do with my questions as well. If so, let me know.
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Old Oct 17, 2004 | 01:57 AM
  #2  
gta324's Avatar
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Joined: Aug 1999
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From: sweden
Car: GTA -89
Engine: Blown 415"
Transmission: 4L80E
Axle/Gears: Strange 12-bolt
1. If your Idle speed is below 5.16.8 Low CL Speed (RPM) you will be in open loop.

2. maybe depending on your setup, if you are running for ex. a big cam with alots of overlap, you will get alot of unburnt fuel on the O2 sensor and the ECM will take out fuel in idle this could lean out the cylinders or causing a unstable idle. I would tune idle in open loop and get it as good as possible, probably a little rich..

/N.
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