How do i fix my car from shuting off with the ac is on, when rolling to a stop, and pressing in the clutch and letting the car out of gear at just above 1000 rpms?

 

you do tuning or any sort of timing/afr changes?

 

my tuner does. The car runs well without the ac on. When the ac is on the car likes to shut off when coming to a slow low rpm stop while taking the car out of gear with the clutch.

 

Do you have large cams? Use Evoscan with the SAS actuator and make sure the idle is set correctly using the BISS on the throttle body. Also check for vaccum/boost leaks. Low vaccum with a leak will cause havok on the MAF reading. I have kelford 272's and I used to have some major stalling issues. Just tune it out. Also raising your idle speed to ~900 will help, but will remove the loping sound that large cams produce.

 

Yes im running large cams, fp4r cams. Are you saying that, maybe I need to unscrew the biss screw further out. And then have my tuner set my idle to around 900 rpms through the ecu, to prevent stalling issues with the ac on? By the way im on speed density on the syock ecu.

 

Yeah, activate SAS mode and adjust the BISS screw out to increase base air flow. The car will probably die when you turn on SAS mode, so give it a turn or two when it does, and try again until you get it right. Use the evoscan logging with engine speed to get the rpm exact. Also, do it with the engine at normal hot temperature.

 

You cant reflash your own ecu? You should really invest in an open port cable dude. That was the 2nd thing I got for mine. And a wideband!

 

I cant reflash my ecu I dont have the cable or software on my laptop. I have a wideband only because my mechanic and tuner said I need one. Im not really into guages.

 

Well yeah, but you have to monitor your engine. I don't like flashy crap, but atleast boost, wideband, and oil pressure. Gotta have them. So without a laptop, using evoscan to turn on SAS mode is pretty much not gonna happen. Just give the BISS a few turns out and see how it reacts. The idle will go up, and then come back down as the ecu compensates. Just don't go too high, or the ecu wont be able to bring it back down, or you'll get a P0505 IDLE air control check engine light. I actually have that one on right now because the weather changed and my BISS is set too high. Good luck!

 

If I bring the biss screw out a little, will it hurt my cold start up? meaning will my car not hold its own idle without me pressing down the pedal untill the car warms up?

 

I dunno if you should just start changing things. It sounds like you've had a tuner do most of the work this far, and it might bet better to let him handle it still. One thing that can happen on EFI cars is that if the timing is set to MBT throughout the rpm range INCLUDING the idle rpms, you can have a lot of trouble with things like a/c. If you don't have that extra pool of torque to pull from, the car can die when you switch A/C on for example. This is why people pull a little bit of timing in the low low idle rpm range, for a cushion.

That BISS screw is something I'd not want to adjust unless it's been previously adjusted. You can change the idle in ecuflash and stuff with software, so no reason to do it on the screw is my take. How hard is it to stop by the tuner and have him raise the idle rpm?

 

My tuner is telling me that he already did that, he says that he tells the car to idle at 1000 rpms and it listens.

 

The issue is when the ac is turned on and you take the car out of gear at just above 1000 rpms coming to a stop the car will stall.

 

subbing, my car does the same.

i have:

and this is my timing map:



car still stalls when coming to a rolling stop with AC on.

any ideas?

 

Are you on speed density? Also what fuel are you using with that high octane map? My tuner and I are going back to a maf to try and see if it will fix the issue I am having with the ac on. If not I'm guessing all we can do is raise the idle.