Lean spot when cold

[kostelacd69]

Ok guys I am in need of some help. I am having some trouble with a lean condition when engine is cold. I will post a log and 2 tunes (one tune is a stock OS and the other is a COS3). Both of the tunes did the exact same thing. The was recorded on the COS. Once the truck has been running for say 30 secs it doesn't do it again. Let me know of any thoughts.

[kostelacd69]

Anyone?

[joecar]

I'm looking at it, where RPM flatens a little while throttle is still going up...

WO2AFR1 goes lean on throttle opening...

try playing with A0008 at around 90*F.

[kostelacd69]

Would that explain commanded AFR at say 13 but the wide band shows 17? Would A0008 just change the commanded AFR?

[joecar]

Would that explain commanded AFR at say 13 but the wide band shows 17? Would A0008 just change the commanded AFR?

Yes, it changes the commanded AFR

( it multiplies the commanded EQR from B3647 )

[kostelacd69]

That is what I'm saying. it is commanding 13 but doing 17. So changing a0008 will only lower the commanded but wont fix the actual afr right? Also note in the stock OS it did the same thing and the OS doesn't have a0008.

[joecar]

A0008 should fix the AFR.

[joecar]

Can you take another log, replace GM.AFR with GM.EQIVRATIO, and add EXT.WO2LAM1 and EXT.WO2EQR1.

[kostelacd69]

I do not have WO2EQR1
I Have Lambda Not EQ Ratio

[joecar]

Ok, log EXT.WO2LAM1 (you should have EXT.WO1EQR1, all the EXT.WO2xxx pids are a function of V2 serial comms connection to wideband).

And GM.EQIRATIO (instead of GM.AFR).