How can I idle in open loop?

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04-01-2007, 09:26 PM

Blazin4x4

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Car: 1988 Chevy silverado K5

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Transmission: 700 r4 with corvette servo and shift kit.

How can I idle in open loop?

I know it invovles changing some delay paramaters but which ones and what do I change them to?

I'm running a 7747 with the amur bin and the 7747.mine ecu file for an .xdf.

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04-02-2007, 08:22 AM

RBob

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Re: How can I idle in open loop?

Here are the values GM used in one of the BBC open loop idles:

Code:

;----------------------------------------------
;
; OPEN LOOP IDLE CALIBRATIONS
;
;----------------------------------------------
LD29E:  FCB  10          ; 10 MPH, OPN LP IDLE THRESH
LD29F:  FCB   6          ; 2%, OPN LP IDLE THRESH TPS
LD2A0:  FCB  38          ; 950 RPM, Open loop RPM thresh IDLE OFF
LD2A1:  FCB  56          ; 1400 RPM, Open loop RPM thresh IDLE ON
LD2A2:  FCB   0          ; 0 Sec's, Open loop IDLE AFR Ratio enable TIME DELAY
LD2A3:  FCB   0          ; 0 Sec's, Open loop IDLE AFR Ratio TIME DELAY
LD2A4:  FCB 140          ; 14.0 Open loop AFR MAX AT IDLE
;----------------------------------------------

The BIN address is as shown without the leading 'LD' . So the first parameter is at BIN addy $29E. The values are shown as they are in the BIN, but in decimal. If these parameters are not in the ECU/XDF file, convert the values to hex and use the Hex Editor to enter them.

RBob.