Idle with Airconditioning

[Mad_Trbo]

I have been trying to get my air conditioning in order with little success.

I think I am going to have to have the whole system replaced but that is another story. Basically when I am idling and the a/c is on I am having an issue where the car wants to die.

FAST XFI has a provision where you are supposed to be able to increase the idle when the AC is detected. I try to increase idle by approximately 100 - 200 rpm but I get no results. I track AC detect and can see where the EMS is picking up the AC but no increase in idle. Could this mean I have an issue with the IAC?

Idle otherwise works well, no hunting, I have it set @ 900 and it holds it well.

 

[Mad_Trbo]

Idle A/c Fast Xfi

Any ideas board?

 

[Otto J]

You must add a wire to the ecu (pin A24)that grounds when the a/c is turned on.This is how the ecu knows you turned the a/c on.You will need one of the XFI style pins.I have them or Cal can send you one.

 

[Otto J]

If you are using a jumper harness,Double check to see if there is a wire going to that A24 now.If there is make sure it grounds when the A/C is turned on

 

[Mad_Trbo]

I found a AC Detect feature and it is turning on when the AC is on. So the harness I have does have this feature, I just needed to make some changes to the idle parameters.

What is weird about this car is how the load changes with the AC. I can't get the fueling right, it seems to share the same load characteristics as without the AC. This makes my fuel rich and requires the EMS to pull greater than 5% when I am not running the AC.

I tried to rescale my KPA up through 100 for every 20 KPA but this doesnt help.

Is there anyway to add a higher level of ganularity to the VE table. I would like to have my KPA increase in increments of 10 up through 300 KPA??

 

[Otto J]

I found a AC Detect feature and it is turning on when the AC is on. So the harness I have does have this feature, I just needed to make some changes to the idle parameters.

What is weird about this car is how the load changes with the AC. I can't get the fueling right, it seems to share the same load characteristics as without the AC. This makes my fuel rich and requires the EMS to pull greater than 5% when I am not running the AC.

I tried to rescale my KPA up through 100 for every 20 KPA but this doesnt help.

Is there anyway to add a higher level of ganularity to the VE table. I would like to have my KPA increase in increments of 10 up through 300 KPA??

Well there is only 16 ve boxes,so no you cant.That would require 30.Are you running close loop at idle?

 

[Mad_Trbo]

Well there is only 16 ve boxes,so no you cant.That would require 30.Are you running close loop at idle?

I know this but with my AEM I can change the number of grid points.

No I am not running closed loop in idle, Before A/C I did not figure I needed to, perhaps I'll give it a try.

 

[Otto J]

Depending on how much boost you run,you can rescale the kpa values where you need to tune for a better idle.