S4 T2 Vacuum ports?!
#1
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S4 T2 Vacuum ports?!
Alrighty. So I had my BOV and boost sensor tee'd from the vacuum port under the BAC. It all seemed to work as intended. BOV went pshhh
I put in my AEM truboost today and figured hey, why not run each vacuum line to its own port!
I ran the lines like so:
Vacuum port under BAC -> Boost gauge
Top port on front of intake manifold (of the 3, by the throttle body) -> BOV
Middle port on front of intake manifold (of the 3, by the throttle body) -> Boost sensor
All other ports are capped.
Drove it home, did a few pulls and noticed that the BOV is no longer pshhh-ing as loud.
Was wondering if there's something up with those three front ports.. Any advice as to how I should run my lines?
I put in my AEM truboost today and figured hey, why not run each vacuum line to its own port!
I ran the lines like so:
Vacuum port under BAC -> Boost gauge
Top port on front of intake manifold (of the 3, by the throttle body) -> BOV
Middle port on front of intake manifold (of the 3, by the throttle body) -> Boost sensor
All other ports are capped.
Drove it home, did a few pulls and noticed that the BOV is no longer pshhh-ing as loud.
Was wondering if there's something up with those three front ports.. Any advice as to how I should run my lines?
#2
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switch the boost gauge with the BOV and you will find out
#3
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This is exactly what I planned to do, was just wondering if anyone had input regarding the matter.
Anyway, I fiddled with it after work yesterday and found out that the top port of the three ports in the front pulls no vacuum at idle and builds vacuum. The bottom port of the three is a normal vacuum port, good candidate for a BOV. I didn't check the middle one but I have a feeling it's like the top port.
For future reference for anyone else, I ran my vac lines like so.
Port under BAC -> boost gauge/boost sensor (tee'd so I can see exactly what the ECU is seeing.
Lowest port on the front three by throttle body -> BOV
Anyway, I fiddled with it after work yesterday and found out that the top port of the three ports in the front pulls no vacuum at idle and builds vacuum. The bottom port of the three is a normal vacuum port, good candidate for a BOV. I didn't check the middle one but I have a feeling it's like the top port.
For future reference for anyone else, I ran my vac lines like so.
Port under BAC -> boost gauge/boost sensor (tee'd so I can see exactly what the ECU is seeing.
Lowest port on the front three by throttle body -> BOV
#4
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if you took it apart and looked at that black spacer thing, you'd see that the ports go to different places. they have it set up so that most of the rats nest doesn't see boost, only vacuum.