My car is lean in the morning

[wesam]

After tuning my VE table i noticed that the car is running lean at high weather temperature
and when drive it in the evening its running in the accepted range 14.6-14.8
but in the hot weather its running in the 15.5 range
what could i do in the tune to fix this issue
should i change the B4901 ?

[joecar]

wesam,

No, don't change B4901... that table models how IAT is influenced by ECT.

Post your .tun file and some logs.

[wesam]

This is the tune file and two logs log 41 is in hot temp
log 42 is in the same day but in the evening

[joecar]

I'm looking at those files, but I'm not sure yet...

41 is the hot temp log and it looks like it's running richer than commanded...

[wesam]

Joe the problem i used to see is when i check the Wide band map after a trip in ht weather it seems that all cells above the normal by one complete point (15.5 AFR )
but when i park the car and drive it in the evening at the same road at the same driving habits it seems that all cell going back to nearly 14.5-14.8 range

[WeathermanShawn]

You are running OLSD (Non-Custom OS) correct?

What temperature did you perform your AUTOVE? Was in on the street, or controlled ECT and IAT on a dyno?

On a street-tuned OLSD, a custom OS will address temperature bias, or just go CLSD. It will trim and you will never have to worry about it..of course that is all user preference. Just an opinion..

[joecar]

I see some things... as IAT increases the wideband AFR gets leaner...

Hmmm, might want to try AutoVE again, try to keep throttle more steady and open it progressively (i.e. not snapping it open), use the brakes to hold you back and to load the engine; be sure to apply the transient filter.

Just be sure to avoid or filter out any stoich cells in B3605.

[joecar]

This OS is 01250001/COS1 and it doesn't have many custom tables...

You might want to try 01250003/COS3 and have a play with table A0014 IAT VE Multiplier.

[WeathermanShawn]

I see some things... as IAT increases the wideband AFR gets leaner...

Hmmm, might want to try AutoVE again, try to keep throttle more steady and open it progressively (i.e. not snapping it open), use the brakes to hold you back and to load the engine; be sure to apply the transient filter.

Idle was always a problem for me when occasionally I tried OLSD (non-custom). Wow, with that IAT & ECT, that DYNAIRTMP would really be high! I think my record IAT has been 167F. OP, I see your IAT is way up there too?

Joe, is he Custom OS? Would that also take care of that heat soak?

[WeathermanShawn]

This OS is 01250001/COS1 and it doesn't have many custom tables...

You might want to try 01250003/COS3 and have a play with table A0014 IAT VE Multiplier.

Thanks for the clarification. Sorry I stepped on your response..