Idle air control..Richard or Clint

[QWKSNKE]

Ok so I am off work today due to it being spring break for my daughter. Decided while she is at the neighbor's house playing that I would attempt to play with the idle air settings and scale my load settings down. (since I idle at 41% load)

I followed the idle setting instructions that is in the help section of the EEC Analyzer. Pulled the timing spout out and unhooked the IAC. Adjusted the screw until my car would idle (high 700's) so that the car would idle (Idle in the tweecer is 896 rpm). My IAC was running at a 61% duty cycle.

After getting the idle screw adjusted where it would idle, I proceeded to datalog and slowly bring the car up in 100 rpm increments to 2000 rpm. Entered the datalog into Analyzer and made the suggested adjustements.

1st question.
Why are there so many cells with suggested info, when there are only 3-4 allowed in the particular Function of the tweecer. Analyzer only gave info up to about 760 rpm. Why not go up to 2000 rpm? Do I just take an average and input that into the low rpm column of this function?

2nd question.
Why is it after I performed this change, that my car idles around 1300 rpm with the IAC and timing spout connected to their rightful areas? Is this a function that has to be numerous times to get 'dialed in'? With the items removed i had to run the idle screw in a good bit to get the car to idle.

[86GT]

With the load in the 40's at an idle the ISC logic is not in the adaptive mode. The idle must be in the 20-30 range.

Question 1:
The EA will calculate an entire line in 100 rpm increments. Since you are able to enter in RPM and air flow into the tweecer I gave the user the option to select which values they wanted to use.

If you ramped up the RPM in the correct increments then it should have gone to 2000 like you stated. If it did not then you must not have been on the 100 RPM increments, meaning 700,800,900 and so on. If you were at 750, 850 950, it will not know which to round up or down.

Question #2
Remeber the ISC stuff has adaptive learning, so if you do not clear it it will use those values.

You stated that you had to set the screw up quite a bit. This means the ISC must have had a high DC when it was idleing before. Lets say it was around 50%. Since the normal is around 35% the error was 15%. This is stored in the KAMRF table. Now when you adjust the TB air flow and ISC curve the error maybe less, but the KAMRF will add the value stored in KAM. This will result in a high idle. If you left it that way the adaptive strategy would eventually correct it. The catch is that with the idle load so high the adaptive was not enabled.

Hope all that makes sense.

[QWKSNKE]

With the load in the 40's at an idle the ISC logic is not in the adaptive mode. The idle must be in the 20-30 range.

Question 1:
The EA will calculate an entire line in 100 rpm increments. Since you are able to enter in RPM and air flow into the tweecer I gave the user the option to select which values they wanted to use.

If you ramped up the RPM in the correct increments then it should have gone to 2000 like you stated. If it did not then you must not have been on the 100 RPM increments, meaning 700,800,900 and so on. If you were at 750, 850 950, it will not know which to round up or down.

ok, that is what my problem was. Now my problem is that i cannot idle the car, due to the cam, in even 100 rpm increments. But i will go try again.

Question #2
Remeber the ISC stuff has adaptive learning, so if you do not clear it it will use those values.

You stated that you had to set the screw up quite a bit. This means the ISC must have had a high DC when it was idleing before. Lets say it was around 50%. Since the normal is around 35% the error was 15%. This is stored in the KAMRF table. Now when you adjust the TB air flow and ISC curve the error maybe less, but the KAMRF will add the value stored in KAM. This will result in a high idle. If you left it that way the adaptive strategy would eventually correct it. The catch is that with the idle load so high the adaptive was not enabled.

Hope all that makes sense.

yes, as i mentioned in the original post, my duty cycle was at 62%.

i will go 'clear' the EEC and try again right now