a/c kills my idle.
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From: Michigan (Macomb or Lansing)
a/c kills my idle. Torquer v3 cam (231/234 .644/.598 111lsa). The car idles reliably at 950 rpms with mostly stock settings for idle. I have my ve table tuned, maf table, RAF, idle is 950 for a/c off and 1000 for a/c on. Running 28* spark at idle.
I turn the setup on and the rpms slowly drop till it stalls.
What should I do to correct this?
I turn the setup on and the rpms slowly drop till it stalls.
What should I do to correct this?
What software? you basically need to add air to the adaptive airflow table. In gear AC on.
You also may need to tweak some other things, depending on where you IAC is at idle without the AC on. Post the tune...........
You also may need to tweak some other things, depending on where you IAC is at idle without the AC on. Post the tune...........
In HPT under tq mngmnt (NOT trans) there is a accessory tq loss model (engine>tq mngmnt>Engine tq) there is a table for AC Tq vs. AC Pressure that can be worked, as well as AC inertia tq. There is a ramp in and ramp out setting for it as well. It mostly adds IAC, but it does at just the right time, with the AC clutch.
upping the inertia tq seems to help if you a hard dip as soon as the compressor comes in, if it just gets weaker and lower, the AC tq vs. pressure table adds airflow the entire time it is engaged and allows you to ramp the air in and out as you need to keep things steady. You just need to play with a bit, it's better if you figure it out then if I tell you where to put your tables so that you can see how they work, fix your issue, and gain understanding. Log and you can see the IAC step up. Look at it now (pre-change) and then try adding 20% to the AC tq vs pressure and see how that does. The ramp in and out values and times can be worked to keep things steady as well.
I just went through a serious of issues with this as well, when running the AC, my idle would go super lean, and then wouldn't hold idle while driving, always stalling. Well, after messing with all of those torque modifier tables, adding more air etc... I found that there was nothing that helped that idle issue. Finally, as a last ditch effort, I up'ed the VE table at the idle position when the AC is on, and bam, solved my problem. I'm running an OLSD tune, so I have no O2 sensors compensating for that extra airflow with extra fuel haha. Do you have a log file of the problem you're having? Also, what is your AFR when you flip on the AC? What do your IAC counts move too, and what is your target idle's with and without the AC on? Are you using EFILive or HPtuners?
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If you jack that table up too high and the ITs go really negative, it can make the idle sag pretty good when the compressor kicks out and you are left with them quite negative but they need to be closer to zero, assuming your idle air had been properly tuned. They move pretty slow.
