Stalling upon deceleration or when coming to a stop...Help!

[Jeff@Slowboy]

First I'd like to start off with the mods:
-small 16g
-sbr 2g fmic with ic pipes and hks bov venting to atmosphere (apparently this is a bigger deal than I thought)
-apexi n-1 exhaust
Bone stock besides for that, I use the car as a daily driver, the only reason I even upgraded was b/c my stock t25 blew and my buddy had all the other parts so i got them for free.

My Problem:

Doesnt happen all of the time, but happened consistently today when i was stuck in traffic. Only when the car is in D (its an auto) when I come to a stop after driving for a little, or I simply just slow down to go over a speed bump for example, the car sputters and unless I sit on the brake and gas at the same time it will stall. But it will start right back up.

Any ideas? possible bad MAF? could it be the bov b/c it isnt recirculated?

Thanks in advance!

 

[cc4ever]

Sounds like the normal problem of using an open BOV after the maf. Try driving and slowing down without blowing off, then try doing it and blowing off before deceleration. Go up to only 20 mph and come to a complete stop. If it only happens during the latter of the two then it is just the open BOV

 

[Gromit]

could it be the bov b/c it isnt recirculated?

Bingo! If you search for "venting to atmosphere" you'll find oodles of threads on this topic. Many will say they do it with no ill effects or only occasional problems. By not recirculating you're losing air that has already been measured & reported to the ECU. The amount of fuel the ECU told the injectors to add is now incorrect for the amount of air you really have, causing you to stall. If you really want to vent then look into a GM MAF as it allows you to run blow-thru style.

 

[xioca]

It needs to be recirculated as mentioned, you could always set your idle a little higher on the BISS skrew and it will most help it from stalling when coming to a stop.

 

[Jeff@Slowboy]

Great guys thanks, Xioca any how to on the BISS screw adjustment?

 

[xioca]

Not actually sure that it works now that I think about it. But in my case I turned my base idle down about 300 RPM from what it was set at before hand, and when I tried to drive it with a vented BOV for shits and giggles I stalled it 4 times getting out of my driveway. Yet before I drove it for a day without it stalling it once.

The BISS adjustment skrew is located on the throttle body just in front of the emission lines. You back it in or out with a skrewdriver and it adjusts your idle. Pretty simple but If you don't get it I can probably explain it a little more if you want.

 

[xioca]

Disregard that information, i just looked it up that it was different to do so on a 2g. I'll read up on it and post a like of two if I can find any.


http://www.dsmtuners.com/forums/showthread.php?t=234723&highlight=BISS

I read through that and confused myself. I don't really know, I always thought it was as simple as adjusting it, well at least my idle seems ok. Sorry I couldn't be more helpful.

 

[Jeff@Slowboy]

Thanks man i really appreciate it! I have to fix the return line on my car tonight so I dont have much time to be searching around. I'm glad that it isnt something more difficult.

I have seen pics of an hks bov with a little tube coming out of th eend of it to recirc it. Is there a vendor that sells it or is it just a little pipe that was fit in there?

 

[xioca]

You could probably fab one up custom if you wanted, but if you'd like to buy a kit here you go...

http://www.hksusa.com/products/?id=799
There's also one at...
http://www.dejonpowerhouse.com/


installation is http://www.dsmtuners.com/forums/showthread.php?t=133499