Aircon issues on link g4x

[Island_Racer]

I have a link g4x running, car is running fine. Just that the ac when turned on “works”, cools and everything, however the ac idle-up does not activate. I simply have to suffer a crappy idle (when at idle).

any idea why the ac idle-up doesnt activate when the ac is turned on?

[Vaughan]

Attach a copy of your tune and a PC log of the engine running with AC off and then the AC being turned on

[koracing]

Your ecu model is ST205X?  If so - the 3SGTE ecu doesn't control the AC per-se, but you do need to make sure you're seeing the AC active request on your digital inputs when the AC is turned on.  You should be able to set up link idle control to idle up when ac is active as long as that input is being triggered.  The factory AC idle up comes from the AC amplifier in the 3SGTE applications, and not the ECU, but there are some versions that require input from the ecu to the AC amplifier to control things.  That being said, it is possible to make the amplifiers work stand alone in many cases so that they will trigger the idle up solenoid on their own without input from the ECU.  As @Vaughan said though, it would be best to post up a copy of your tune and a log if you need further assistance.

You posted almost the same thing in September here: 
 

 

Did you ever follow any of the requests in that thread for a PC log?

In your tune on that thread there was no idle up configured in the idle settings for when the AC request was active.

[ellisd1984]

I did a post on hete a while back. The pin the link wires to is a ac cancel ssignal and ultimately has now direct control over the compressor clutch.  This means the delays ypu can program for idle up before the clutch engages don't work properly.  

 

[koracing]

I get AC request just fine on the 3SGTE ST185x and ST205x as pinned from Link for the AC magentic clutch engaged signal (Pin AC1 or AC) - this taps into the AC magnetic clutch engagement wire in the case of an MR2.  The ACT pin isn't connected on the link.

[ellisd1984]

 

 

 

 

 

[ellisd1984]

I should probably add I didn't have the stock idle up valve which was probably causing the issues. 

From what I can tell the Link doesn't get the "AC Activate" signal from the AC button when you push it.  It get the signal from the the feed leaving the AC amplifier that activates the clutch.  

If you've got the stock Idle up valve then there is no issue as the AC button Activates the Idle up valve, rev's increase, clutch engages the same time as the Link get the AC signal.

If the idle up valve isn't there, the Link doesn't get the signal until the clutch engages so it has no time to stop the engine stumbling.

 

 

[koracing]

I don't typically have a problem even without the factory idle up solenoid.  You could theoretically wire up the factory idle up to be triggered by an output on the link.  Increase base idle air bypass to about the idle speed you want warm with the idle control motor fully closed or plugged and then you shouldn't have stumbling even with some delay in engagement.

[Island_Racer]

On 2/28/2023 at 11:04 AM, koracing said:

Your ecu model is ST205X?  If so - the 3SGTE ecu doesn't control the AC per-se, but you do need to make sure you're seeing the AC active request on your digital inputs when the AC is turned on.  You should be able to set up link idle control to idle up when ac is active as long as that input is being triggered.  The factory AC idle up comes from the AC amplifier in the 3SGTE applications, and not the ECU, but there are some versions that require input from the ecu to the AC amplifier to control things.  That being said, it is possible to make the amplifiers work stand alone in many cases so that they will trigger the idle up solenoid on their own without input from the ECU.  As @Vaughan said though, it would be best to post up a copy of your tune and a log if you need further assistance.

You posted almost the same thing in September here: 
 

 

Did you ever follow any of the requests in that thread for a PC log?

In your tune on that thread there was no idle up configured in the idle settings for when the AC request was active.

Hey, I finally got around to looking at this car again. See attached the pc log for the session with the ac being tuned on and off. Also see the current setup of the parameters. Sorry for being so tardy with responses.

I didn't do the setup myself so possibly you could walk me through the idle settings to initially use.

 

ac log file.llgx current setup.pclx

[koracing]

First: why is there no lambda?  Hard to say if your fuel is tuned properly in the idle region without any lambda data.

Second: Your continuously hitting the idle MAP lockout - so you need to raise that from 50kpa to something like 75kpa. 

At no point in your log are you getting the AC request either.  Is the AC actually engaging?  Idle ignition control would probably help stabilize idle as well but it is disabled. 

[Island_Racer]

4 hours ago, koracing said:

First: why is there no lambda?  Hard to say if your fuel is tuned properly in the idle region without any lambda data.

Second: Your continuously hitting the idle MAP lockout - so you need to raise that from 50kpa to something like 75kpa. 

At no point in your log are you getting the AC request either.  Is the AC actually engaging?  Idle ignition control would probably help stabilize idle as well but it is disabled. 

When the button is pushed in the car the compressor activates and the air starts to cool….so “it works”, its just that the idle up (that i can usually hear open up) never opens up.

 

i will raise the ie map lockout to ur recommended value.

i have an aem uego installed, can use either the serial pin or the 0-5v analog pin to connect to the g4x? Or no?

[koracing]

You'll want to use the 0-5v analog pin and run it to one of the analog inputs on the ecu - if you don't have an expansion harness you can read it on the original o2 sensor signal wire which is connected to AN Volt 1 input.  If it's an AEM wideband with only a single wire analog output (white wire) and no brown ground reference wire, it's likely there's going to be a mismatch in calibration between the gauge display and the reading in the ecu even after entering the recommended calibration.  You'll have to tweak that calibration in the ecu to match the gauge.