IAC counts

[hquick]

Can someone please tell me....
When in park...engine at op temp...what should IAC counts be?
When in gear...engine at op temp...what should IAC counts be?
Is it a matter of adjusting the set screw to get the counts into the correct range?
In gear...I'm seeing around 57 counts. In park....I'm seeing as low as 7 counts.

Thanks

[SSpdDmon]

It's been a while since I've worked with an A4. I'd say, try adding a little timing for idle in gear. This may help bring your IAC counts up some and reduce the delta. Then, I'd target ~50 steps for in park and ~80 steps for in gear. Basically, you want enough padding below your current steps to be able to allow the IAC some control in the event it needs to block airflow to the engine.

[hquick]

So....I should first set the blade to fully closed and then reset the TPS?
How do I actually increase/decrease IAC counts? Just by adjusting the set screw?

Thanks

[SSpdDmon]

I would use the bi-directional controls and slowly close the blade with the set screw until you see the IAC counts creep up. Closing the TB increases the IAC counts and opening the TB reduces them. You shouldn't need to mess with the TPS sensor.

[hquick]

OK....rain finally stopped for 10 mins so I decided to tackle the idle issue
Closed the TB completely (wound the screw right out) and then just wound it in enough to make sure the TB blade wasn't sticking.
I then 'reset' the TPS and the IAC and started logging.
At fully warm idle....in park I tried to get the IAC steps to 50 and 80 in gear.
I added one or two degrees of timing and then played with desired airflow.
I can't seem to get the IAC counts above approx 55 and 75. If I do...the Burb has alot of trouble finding idle on a re-start and will mostly stall.
It seems to be good at 55 and 75.

[macca_779]

Howard I'm not a fan of messing with the set screw as if you open it enough it will eventually give false TPS values. Rather I drill out the base hole in the Throttle blade. I just work up slowly until I get a result where idle can be maintained with approx 70 steps.

[hquick]

Thanks Macca.
There's alot of talk about 'to drill or not to drill'.
These TB's don't actually have a hole at all.

[5.7ute]

Hi Howard. To get my iac counts where I wanted them involved both adjusting the set screw & opening the hole in the throttle blade slightly. As sspdDmon has stated you want the iac counts where they have best control over airflow, between 40 to 80 counts. But remember that this is just a base position for the iac valve to go to. Idle speed is mainly controlled by timing as the iac moves too slow to have any real effect on this.

[SSpdDmon]

OK....rain finally stopped for 10 mins so I decided to tackle the idle issue
Closed the TB completely (wound the screw right out) and then just wound it in enough to make sure the TB blade wasn't sticking.
I then 'reset' the TPS and the IAC and started logging.
At fully warm idle....in park I tried to get the IAC steps to 50 and 80 in gear.
I added one or two degrees of timing and then played with desired airflow.
I can't seem to get the IAC counts above approx 55 and 75. If I do...the Burb has alot of trouble finding idle on a re-start and will mostly stall.
It seems to be good at 55 and 75.

Hi Howard. To get my iac counts where I wanted them involved both adjusting the set screw & opening the hole in the throttle blade slightly. As sspdDmon has stated you want the iac counts where they have best control over airflow, between 40 to 80 counts. But remember that this is just a base position for the iac valve to go to. Idle speed is mainly controlled by timing as the iac moves too slow to have any real effect on this.

WERD...the numbers I threw out were merely targets. If you hit 55/75, you're there.

If you're having startup stalling issues, try adding a little airflow to the startup friction tables under idle>startup for the coolant temps where you're seeing problems.

[hquick]

Thanks again.
When I start the Burb when warm (cold starts are fine) rev's go high....low (almost stalling)...high...low until it settles.