Finally resolved the stalling issue by moving the maf to blow thru as opposed to draw thru and am able to move onto other things! LIKE, COMMENT, SUBSCRIBE. Instagram: Builtlikethis
So, the BOV wasn't connected to a vacuum source before this change? Or am I misunderstanding what you're saying? I have a PT5857 and a Tial 50mm BOV (vented to atmosphere). At idle, my BOV is open and blows air out. This is normal because what actually causes a BOV to open is intake manifold vacuum. So, most BOVs will vent some air out of them at idle. Here's a breakdown of the stalling issue: The reason that people have issues with stalling on MAF cars and atmospheric BOV's is due to air being vented that has already been read/metered by the MAF. For example, let's say you're having some fun and getting into boost. During shifts, the throttle plate closes and the BOV opens. So, suddenly you have all of this pressurized air being released that has already been metered by the MAF. But the ECU does not realize this because it is going by the MAF readings which indicate a bunch of air just made it into the engine. What you end up with is an overly rich condition which leads to stalling. When people talk about recirculating their BOV, they recirculate it to a location on the piping BETWEEN the MAF and the turbo inlet. By doing this, any air that is vented by the BOV is just recirculated back into the engine. Since it comes in after the MAF, it all stays within the closed-loop system. With any MAF setup, any little leaks between the MAF and the intake valves become a problem because you are releasing or sucking in UN-metered air. The other thing to pay attention to with a MAF setup is how you have your PCV plumbed/routed. Both the valve cover vent and the PCV valve need to be hooked up AFTER the MAF. If you have one side hooked up and the other side unhooked (such as a breather filter on the valve cover), you're going to have the same problem with metered air entering/exiting the setup. Also, if you vent both ports to atmosphere, it won''t be an issue.
ya vacuum line wasn't hooked up before this. so it couldn't have been the problem. but I agree with everything you said. When I had the line connected it made it even worse. As for the PCV I want to look into getting an oil catch and routing it properly. thanks for the input!
I have the same car. But mines in mph an the "Grey interior" with 1 owner title. Saw your video when you first got it. Glad to see uve been making progress
It stalls because the BOV vents to atmosphere and since the MAF already metered that air it thinks its going through the engine, but in reality its gone and runs to rich and stalls. Now yours doesnt stall because the BOV is gone.
The job of the BOV is allow the pressurized air in the intake system to have somewhere to go when you let off the throttle. This allows the turbo to continue spinning at a high RPM. If not, the turbo will continue to build boost in the intake and slow the turbo way down very quickly. It isn't as bad at low boost levels but this get worse the higher the boost levels are. google turbo fluttering and you will be able to hear what i'm talking about. All that air you are venting into the atmosphere was already picked up by the MAF sensor so it was trying to add the extra fuel causing the engine to die at high boost levels. Now that you moved the MAF closer to the throttle, it is only adding what the engine is taking in. The BOV should not leak during pressure and it should not leak during idle. Only under high vacuum should it be open.
out of curiosity, why did this solve the issue? just wondering bec I have a draw through on my rb20det and it does the same exact thing as yours was doing. aka stalling when boosting then shifting to neutral unless revved until idle.
BuiltLikeThis if you think of the function of a BOV its job is to vent excess pressure when the throttle closes. Many factory setups send this vented air back into the intake. Venting to the atmosphere does just that and releases that metered air.
make sure to have a good retune if you turn it up to 10 pounds, i wouldn't go past 12 on a stock ka, the ringlands on ka's stock can be weak so 12 is a safe limit. i would definitely hook the bov back up on the other side soon, turbo flutter sounds cool but will kill the seals and bearings in the turbo if there's no where to vent the excess pressure when you let off the throttle. stalling shouldn't be an issue with the blow through now if you hook it back up. The build is coming along great, keep up the good work
for the leak where the weld is there's this stuff made by Permatex it's called The Right Stuff that it is incredible I use it for all sorts of things and it doesn't leak and can be put back into service immediately it's a little pricey but give it a try
It's too late now, instead of cutting up the MAF, you could use a coupler to connect the air filter adapter to the intercooler piping. Just in case you want to revert back to the old setup.
Hey, I was just wondering whether or not you used your wastegate arm to adjust your boost? I want to turn up my boost, but my boost controller sucks (the isr one ironically). How much do you have to turn in the actuator arm to raise the boost by a couple psi? Right now I am hitting 8, but I would like to hit around 12-15. Thanks and keep up the vids.
Hey man, I'm having the same problem on my s14 ka-t. When I let go of the gas while it's under load, it stalls out on me. When you converted to this, did you have to reflash your RS tune?
I think it's just the placement of the maf. where it was before it was where the air was being drawn after the filter and he moved it to where the cold air is being forced into the intake
