Idle AFR and temp

Holden/Delco Tuning. ALDL, OBD 1.5. Circa 1989 to 2004.
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VL400
Posts: 4991
Joined: Sun Mar 01, 2009 4:54 am
cars: VL Calais and Toyota Landcruiser. Plus some toys :)
Location: Perth, WA

Re: Idle AFR and temp

Post by VL400 »

The open loop coolant offset table value is multiplied by the coolant temperature modifier value. This ends up being used as a coolant offset term and is subtracted from the what the target AFR table had, but it will be reflected when logging as a final target AFR that differs from what you have in the target AFR table.

Can try zeroing the 56deg 0.40 value to see if it changes anything, but if your actual AFR differs from the target there is something else wrong.
0081(2)
Posts: 149
Joined: Wed Oct 31, 2012 8:59 am
cars: VY commodore supercharged V6
Location: Sydney

Re: Idle AFR and temp

Post by 0081(2) »

Well i went back over my log and it was out when cold and got a bit better when warm but not where it should have been, then i went back looking for a old log where the idle fuel was where it should have been and i tried a few of those bins and it was still out.

I decided to pull fuel until it was right and i went from (about) 0.963 down to 0.791 in the 800 rpm and 150 - 200 cylair cells which got it where it needed to be. went for a quick drive and everything else was about right.
I didn't think much about it at the time but i did change my fuel pump so it must have been the stronger flow of the new pump that was causing the issue.