Just curious as to where those running blow through mafs are running their vacuum lines to. And I mean both the bigger AAC/AirRegulater line and the vacuum line for the swirl control valve.
Of course you have to move them somewhere downstream of the MAF or it isn't metered air --> idle problems. But can these lines then see boost?
I've been having issues with the BOV and I'm wondering if boost is leaking into the manifold (with TB closed) through these lines. Which of course makes positive pressure and keeps the BOV sealed shut.
Pictures would be sweet. =)
Blow-Thru Q's
Here's how I ran mine. The bigger tube(AAC/IACV I believe) is plumbed in after my MAF right before the throttle body. As for the other vacuum line. Mine is plugged. However, if it was hooked up, it would need to be hooked up before the turbo. Here's a pic of my MAF with the AAC/IACV line plumbed in. Please excuse the leaking valve cover gasket, and dirty nasty engine bay.
PMan_S13 wrote:Hmm,.. you have the smaller vacuum line plugged? Do you have any problems with it running rich at idle?
That line is supposed to be the activator for the swirl control. It's supposed to mix up the air and fuel at low throttle/idle for better atomizing/combustion.
Thanks for the pic btw..
You could always loose the swirl valves completely. Just remove them. Emissions Emissions Emission... this time around I don't care sh** about emissions. :pface
Yeah, that line is for the swirl control valve. I decided to not let it run anymore, hehe. So far I have removed the AIV, removed the EGR and plugged the intake manifold with a custom plug, and rendered the swirl control valve inoperable. Honestly, none of these things made a noticable change in how the engine runs. I passed emissions without the AIV, but haven't tested since then. I think, in my case, that a lot of these "emissions" valves weren't even working very well anymore because of the age of my engine. I always had massive idle problems with them, but without them, the car idles good, still not perfect, but better than before.
andrave wrote:that looks good. who welded your pipes? what welder did they use?
Thanks. Basically my brother did most of the welding, while I cut and fabbed the pipes. Although, you can't tell with that particular pipe, I used mandrel bends, and sections of straight pipe. However, that bend was too severe, so I had to cut several sections to get the bend I needed. We used the welder at the shop he works at. It's a Lincoln MIG, but I'm not sure of the model. We TIG welded the manifold, then ran out of gas, so we MIG welded all the piping.
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PMan_S13
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It wouldn't idle on it's own.
That control valve is basically letting air get in another route around the closed throttle body. That air is metered just like any other intaken air and the ecu responds with fuel. If it doesn't see any air coming in (even if it really is), then the ecu gives no fuel and the car dies.
I had this problem before when I ran my Idle contol lines upstream of the MAF when I first did my blow through.
That control valve is basically letting air get in another route around the closed throttle body. That air is metered just like any other intaken air and the ecu responds with fuel. If it doesn't see any air coming in (even if it really is), then the ecu gives no fuel and the car dies.
I had this problem before when I ran my Idle contol lines upstream of the MAF when I first did my blow through.
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sil80drifter
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PMan_S13
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I don't know SOHC KA's at all, but it should have something very similar.
All motors have to have a way to idle, which is just letting secondary air in when the throttle body is closed. The easiest way to find it would be to look for a big fat air line going from somewhere upstream of the throttle body to somewhere downstream of the throttle body. (And most likely somewhere in the middle it intercepts the control valve.)
On the DOHC the control valves are sitting on the intake plenum just under the intake runners.
All motors have to have a way to idle, which is just letting secondary air in when the throttle body is closed. The easiest way to find it would be to look for a big fat air line going from somewhere upstream of the throttle body to somewhere downstream of the throttle body. (And most likely somewhere in the middle it intercepts the control valve.)
On the DOHC the control valves are sitting on the intake plenum just under the intake runners.