Actual AFR during cold idle

[joecar]

My VE table is dialed in (BEN's AT 1.00 in most places);
during cold idle, my actual AFR is leaner than commanded, and then slowly converges as engine warms up;
What tables are involved here, how do I explain this...?





BEN map of the above log:




BEN map after warmup:

[carneb]

My car does the same. I'dlike to know the answer too.

[Tordne]

All ours do it . In the custom OS3 & 5 I use the A0008 table to command richer mixture till partially warmed up (50*C). You may also be able to do the same by slowing the decay of general after-start enrichment.

Bear in mind that your WBO2 sensor may also not be up to temp straight away and could account for the leanness also, I certainly see that.

[TAQuickness]

This a long standing problem/mystery for SD.

http://www.ls1tech.com/forums/showth...highlight=lean

Don't think it was ever resolved either.

[ringram]

Why worry? As mentioned mine is the same too. I noticed yours looked good Tordne in your logs. I might mess with A008 though as when cold it runs a little gutless.

My logs show a sudden drop, not a gradual richening like that. Ill dig one out to show you.

[TAQuickness]

I believe you will find the IAC steps follow the same slope as the richening. My theory is the fueling doesn't account for the startup and startup friction airflow unless it's observed by the MAF (MAF guys don't seem to have this problem).

[ArKay99]

I had this problem at first too, I run an MAF. I found that if I turn off my A.I.R. to log cold AFR, That fixed my cold lean AFR issues. I was seeing 17:1 or more on my WB.

[Dirk Diggler]

Most of these guy have allready gotten rid of the AIR Pump

[TAQuickness]

Yes, my AIR pump has been on my bench for a while now.

Spare PCM inputs

[joecar]

Yes, my AIR pump has been on my bench for a while now.