Highway Mode in Open Loop
Highway Mode in Open Loop
Does Highway mode work in open loop?
I locked my ecm in to open loop and my highway gas milage sucks. With the wideband I am getting around 13.5 at 2500rpm cruising. I noticed that I had the max map for highway mode set at 43 and at cruising (2500rpm) I am at 45 or so. I think adjusting this will help, but I wanted to make sure it will work in open loop.
I locked my ecm in to open loop and my highway gas milage sucks. With the wideband I am getting around 13.5 at 2500rpm cruising. I noticed that I had the max map for highway mode set at 43 and at cruising (2500rpm) I am at 45 or so. I think adjusting this will help, but I wanted to make sure it will work in open loop.
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From: Chasing Electrons
Car: check
Engine: check
Transmission: check
Most of the time it won't. Need to be in closed loop before hiway fueling is enabled. Although this can vary according to mask.
RBob.
RBob.
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From: Chasing Electrons
Car: check
Engine: check
Transmission: check
Originally posted by jonarotz
Any idea on a 730 8d?
It looks like I just need to fine tune my VE tables.
Thanks
Any idea on a 730 8d?
It looks like I just need to fine tune my VE tables.
Thanks
Code:
LC83D: LDAB L000D ; TIME OUT AFR
BCLR L0037,#$02 ; CLR b1, HIWAY FUEL TMR RUNNING
LDAA #$01 ;
BRCLR L0047,#$80,LC8AB ; Br IF NOT b7, B7 1 = CLOSED LOOP
; .... else
BCLR L003D,#$04 ; CLR IN OPN LP PRIOR TO 
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Joined: Oct 1999
Posts: 6,621
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Car: 91 Red Sled
Axle/Gears: 10bolt Richmond 3.73 Torsen
Running in open loop... why bother with highway mode? Just use the VE table to lean out the AFR at that RPM/MAP until you notice the MAP increasing to sustain that vehicle speed. Don't worry too much about burning the engine up from running lean unless you've got a barn door for a front end and/or a heavy vehicle. If you've got a oil temp gauge I'd keep tabs on it to make certain the temps don't climb.
That's the beauty of open loop, get the perfect AFR at any engine condition
... except if you live in a smog area 
Just an opinion but cool oil temps vs 1mpg on the highway is totally up to you. Balance it out.
That's the beauty of open loop, get the perfect AFR at any engine condition
... except if you live in a smog area Just an opinion but cool oil temps vs 1mpg on the highway is totally up to you. Balance it out.
Last edited by JPrevost; May 19, 2005 at 02:20 PM.
Thats the main reason I locked it in open loop, I know where the fuel is. I just wanted to see if I could lean it out on the highway using highway mode. I will just play with the ve table and find the sweet spot. 
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