Thread: Cold Start Stalling. how many of you out there have it?

so i went out today to start my car to move it...its 50 degrees so its not overly cold but probably the first time i started it in 3 weeks or so... but when i start my car it idles up around 1500rpm the stalls out. when i hold my foot on the gas and try to idle it steady at 1500rpm it holds and then gradually stalls out again.....after i get it started and hold my foot on the gas for it to hold a decent idle, it eventully idles good and doesnt die.... is this a iacv or aac problem? i see this is faily common on our cars was wondering your guy's thoughts

IAA,air regulator, or vac leak are the three most likely candidates, mainly vac leak since it is stalling out. Hows gas mileage? How much psi have you tested your intake system with?

I had it pretty bad in my car but I'm hoping it will be fixed after I'm done with the current rebuild. I'm switching to blow through which should help (less chance for unmetered air problems). I pulled off the ARV and the IACV and took them apart and cleaned/rebuilt them. I also realized I monkeyed up the wiring when I did the swap in 2001. I had the ARV wire hooked up to the knock sensor and the knock sensor wire just hanging, doh! Oh well, it was my first engine swap ever and I was still learning.

I think its iacv/aac. Could also be a vacuum leak.

what size injectors do you have?

i had the same exact problem, even in the middle of the summer. it was a pretty small thing, engine coolant temp sensor. once i replaced that it was fine

as far as fuel system goes, im running

msd 72lb injector
jgy fuel rail
nismo automatic fuel pressure regulator
waslbro 255lph

i definitly think its aac/iacv related rgose damn iacv are a bitch to replace

i know with the calum ecu's for some reason the larger injectors make it harder to start...least that's what i hear.

im running the AEM EMS, i got it started and drove it around a bit, and like most after it was warmed up, i could start it and shut it off fine.

i definitly think its probably the iacv but i would hare to have to replace that on a highport esp

Swap your coolant temp sensor out and the problem will go away. If it was the IACV your car wouldnt idle right even when it was warmed up.

What the coolant temp sensor does is make it so that when the car is cold it runs rich until the sensor sees the temperature its looking for. When it sees that temp(after you hold your foot on the gas for a while) then the car will idle and drive regular.