Startup Friction Airflow Correction table? [Archive]

jnorris

October 30th, 2005, 12:25 PM

Below is on a 98Z28 A4.

Today I played with this table in an effort to correct a warm starting problem and it seemed to work okay. But…
The problem is that when you transition from park to drive or drive to park it seems that the values in {B4343} Startup Friction Airflow Correction table are also added to the {B4703} Desired Airflow table and the IAC counts jump up and as expected the idle increases.
I thought that the values in {B4343} were only applied at startup and for a very short time afterwards as controlled in the {B4344} Startup Friction Airflow Decay and {B4345} Startup Friction Airflow Delay tables.

Does anyone have any experience with the idle start-up tables?

Thanks

John

jnorris

November 3rd, 2005, 02:13 AM

Help a guy out!

bink

November 5th, 2005, 08:09 AM

Help a guy out!

I've used both Friction and Start up airflow to correct the overev on startup ( 90 mm tb). I haven't noticed your situation but I have an M6 (M12 - Z06).
What I have noticed, in the past, is excess table airflow showing up added to Idle Airflow - it really screws with the idle airflow learning (Trims).

Hope this helps some.

Cheers,
joel

jnorris

November 7th, 2005, 03:41 PM

Help a guy out!

I've used both Friction and Start up airflow to correct the overev on startup ( 90 mm tb). I haven't noticed your situation but I have an M6 (M12 - Z06).

What I have noticed, in the past, is excess table airflow showing up added to Idle Airflow - it really screws with the idle airflow learning (Trims).

Joel,

Do you mean excess table airflow values in the Desired Airflow table?

Thanks

John

jnorris

November 10th, 2005, 02:08 AM

Any more suggestions?

John

bink

November 10th, 2005, 05:01 PM

Help a guy out!

I've used both Friction and Start up airflow to correct the overev on startup ( 90 mm tb). I haven't noticed your situation but I have an M6 (M12 - Z06).

What I have noticed, in the past, is excess table airflow showing up added to Idle Airflow - it really screws with the idle airflow learning (Trims).

Joel,

Do you mean excess table airflow values in the Desired Airflow table?

Thanks

John

No - I mean when scanning start up pids ( Start up _DMA and Friction_DMA) . If my engine overreved (4000+ RPM) I would see excess air in the scanned DMAs - on the next start up.
I can't remember if it was start up or friction......but I think it was the friction_DMA.
Odd!!