Raise boost and Gauge goes up?

ayang89

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2003.5 Mazdaspeed Protege #1827
I noticed that when I turned my manual boost controller up that my boost gauge goes closer to 0.

Is that normal?

I turned it back to read -20.

Just curious if that's right.
 
I noticed that when I turned my manual boost controller up that my boost gauge goes closer to 0.

Is that normal?

I turned it back to read -20.

Just curious if that's right.

............................ I'm really interested to see how you have this connected.............
 
And to answer your question, no it's not right... You do not have it installed correctly. I feel like you have your boost gauge > vacuum source > boost controller > vacuum source......
 
I have it

Wastegate - tube to manual boost controller - tube connected to a Y shaped splitter - one splits into a tube for my boost gauge, the other tube Into my intake manifold.
 
Which side is your boost controller on???
 
It's inline in the wrong place. You're cutting the vacuum to your boost gauge is all you're doing...
 
Messed up. It's like this. Just double checked.

Wastegate/tube/boost controller/ to a T splitter, one hose hose goes to my BPV, the other hose goes to the Y splitter, from the Y one goes to my boost gauge the other to my intake manifold.
 
I think you should take that boost controller OUT until you replace a few things... those plastic intercooler pipes for one... I also think you should invest in a vacuum block. that vacuum point is fine but the tube routing is a big of a mess. with a block you can run dedicated lines to everything that needs a vac source.

as long as the boost controller is not behind anything from the wga to the manifold it should work correctly.. not sure whats goin on with your vac gauge unless maybe your wga is bad and leaking. then when you adjust the boost, you adjust how much of a leak you have essentially.

vac block is nothing special. just pick up some small barbed fittings from a plumbing store, some hard plastic or aluminum barstock at least 1/2"thick, drill some holes, tap if you have the tool, otherwise the harder metal will tap the softer metal.
 
I think you should take that boost controller OUT until you replace a few things... those plastic intercooler pipes for one... I also think you should invest in a vacuum block. that vacuum point is fine but the tube routing is a big of a mess. with a block you can run dedicated lines to everything that needs a vac source.

as long as the boost controller is not behind anything from the wga to the manifold it should work correctly.. not sure whats goin on with your vac gauge unless maybe your wga is bad and leaking. then when you adjust the boost, you adjust how much of a leak you have essentially.

vac block is nothing special. just pick up some small barbed fittings from a plumbing store, some hard plastic or aluminum barstock at least 1/2"thick, drill some holes, tap if you have the tool, otherwise the harder metal will tap the softer metal.

Yeah, bought the car like this a month ago. Maybe it is my wastegate. But when I blow into the tube no air goes through?

And yeah. When I adjust boost up, it gets closer to 0. Weird.
 
I would tap the compressor housing and run your controller directly from there to the wga. I'd have to check but I think I only used that source for bov and wga.
 
Ha! You have an MSM cap, too. I had that cap on my car since I got it and never knew where it came from until my buddy got an MSM and says to me one day, "that's an msm cap"...


But back on topic...

I wouldn't even begin adjusting the boost if you're in stock trim. You're just asking for trouble. And unfortunately you're too far away from me for me to buy the car when it sends a rod through the block. So, don't do that.
 
I'm surprised you didn't know that. Pro-tip, there is an allen set screw on the bottom so you can turn the 'mazdaspeed' lettering straight, unlike the 07-09 MS3 cap which is always crooked.

+1 as I said in the other thread, MBCs aren't a great idea with a stock engine. Especially if you don't know what is going on with the car. BTW that is a very clean engine bay, can't believe the wiring harness and parts look so new. Definitely was garage kept.
 
I'm surprised you didn't know that. Pro-tip, there is an allen set screw on...
There was one at some point and time that was probably the correct thread/pitch...... But someone installed one that wasn't the correct thread/pitch and it's also stripped, so I can't get it out. I always have an upside down 'Mazdaspeed'. :(
 
i was actually drooling over his engine bay lol. i dont thing my wires were that nice when i picked it up 7 years ago, at 80km lol
 
I'm surprised you didn't know that. Pro-tip, there is an allen set screw on the bottom so you can turn the 'mazdaspeed' lettering straight, unlike the 07-09 MS3 cap which is always crooked.

+1 as I said in the other thread, MBCs aren't a great idea with a stock engine. Especially if you don't know what is going on with the car. BTW that is a very clean engine bay, can't believe the wiring harness and parts look so new. Definitely was garage kept.

118k Original miles
 
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Can anybody show me a picture of how this should've been set up? I'm still lost.Still a noob to MSPs. I bought a tube to replace and take out the MBC. But I would like to know how it should look like. Haven't found any photos online.
 
The vac line should run off the port on top of the intake manifold to a T fitting, one of the lines off the T runs to the bypass valve, the other runs to the wastegate. The boost gauge should be T'd off a different vacuum line on the intake manifold, avoid running too many sources off the same vac line. A vacuum block on the brake booster vac line is really the way to go so each source can get the same vac reference.
 
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