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Installed A Boost Gauge, Help Figuring It Out Please?


mattsk8

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Wow,was that necessary?

Post your crap in Political or Off Topic where it belongs.

EDIT: I have no patience for BS posts like this. This isn't TurboBricks. The OP has a specific issue, and BS posts do nothing to contribute or help the situation - you can see the crap that follows.

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Matt,

In don't disagree that there is a leak, but I don't think its with the intercooler hoses. Being your vacuum is so low @ idle, the leak would have to be somewhere AFTER the throttle plate ;).

I do agree that replacing your vacuum and TCV hoses with silicone is a good idea. I believe iPd's hose is 5mm, and is very good quality. Not the cheapest out there, but has a heavy wall and is nice stuff. Probably would need 10' or so to do everything, I usually buy a few extra feet to have around ;).

Hope this helps,

Joe

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In don't disagree that there is a leak, but I don't think its with the intercooler hoses. Being your vacuum is so low @ idle, the leak would have to be somewhere AFTER the throttle plate ;)

Curious to understand the reasoning behind this statement. When I've had an IC hose loose, my vacuum has been off at idle as well as being unable to hit full boost and throwing an overboost code.

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Curious to understand the reasoning behind this statement. When I've had an intercooler hose loose, my vacuum has been off at idle as well as being unable to hit full boost and throwing an overboost code.

With the throttle plate closed, the gauge is measuring the suction against the throttle plate. Unless the position of the plate moved, it should remain the same as long as everything after the throttle is tight...

Joe

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My vote is for the short hose between the IAC valve and the Manifold. It would affect vacuum as well as boost. I had mine crack clean open and the car did just this. Look on the underside if it isn't immediately apparent. If not then it could very well be a blown intake manifold gasket or TB gasket. I would also double check the vacuum line for the breather system that comes off the end of the mani opposite the TB just in case it popped off. It'll have very similar results.

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I'm prepared for the worst. I have 2 cans of starting fluid and plan on giving the engine and all surrounding hoses a bath w/ it tonight to try and find leaks. I also (for now) got some cheap vacuum line from the parts store to use; later I'll go over everything w/ the silicone.

Unfortunately if its a leak in any of the IC plumbing, I won't see the Snaab RIP kit until about mid January. Might be a trip to a junk yard to get me by if I find anything obvious there. Hopefully it isn't the actual IC leaking.

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With the throttle plate closed, the gauge is measuring the suction against the throttle plate. Unless the position of the plate moved, it should remain the same as long as everything after the throttle is tight...

Joe

Ok. But the throttle plate isn't fully closed at idle; and there are 4 vacuum lines (PCV, brake booster, Evap, and WGA) that are all post-TB and could contribute to loss of vacuum at idle.

My vote is for the short hose between the IAC valve and the Manifold. It would affect vacuum as well as boost. I had mine crack clean open and the car did just this. Look on the underside if it isn't immediately apparent. If not then it could very well be a blown intake manifold gasket or TB gasket. I would also double check the vacuum line for the breather system that comes off the end of the mani opposite the TB just in case it popped off. It'll have very similar results.

No IAC - this is a ME7 car with an ETM. Pretty obvious from the pictures in the OPs first post ;)
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Ok. But the throttle plate isn't fully closed at idle; and there are 4 vacuum lines (PCV, brake booster, Evap, and WGA) that are all post-TB and could contribute to loss of vacuum at idle.

No, it isn't fully closed, that I agree with. But unless the ETM is trying to counteract another issue, it's as closed as it is on a car pulling 22" @ idle.

As far as the 4 hoses after the throttle, again I agree. That is the point I was trying to make, is that one of those 4 hoses is a more likely suspect than a charge hose leak given the low vacuum readings ;).

Joe

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Given that I've driven ~300 miles with the line from the "bubble" over the ETM missing and still pulled 16-18inhg at idle, I don't think a small line like that would cause a leak of that size.

Matt, if your intake manifold has been off any time recently, check to make sure you didn't pinch the metal support bracket (on the drivers side of the car) between the intake manifold and the gasket. That would cause a large vacuum leak.

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Do you have a short vid of the engine running at idle? I'd look at the check valve fitting off the short hose on the end of the intake that feeds the brake booster. The end cap can crack & present a large vacuum leak, that you may not actually hear. It;'s that long plastic fitting in your pic that your boost vac line is running close to.

I'll apologize to all for the online cussing.

However my opinion remains that non productive posts that clutter so many threads just become an aggravation when trying to scan for info in responses throughout a thread. I don't like to dismiss people, but that does become a tendency after a while.

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Given that I've driven ~300 miles with the line from the "bubble" over the ETM missing and still pulled 16-18inhg at idle, I don't think a small line like that would cause a leak of that size.

Matt, if your intake manifold has been off any time recently, check to make sure you didn't pinch the metal support bracket (on the drivers side of the car) between the intake manifold and the gasket. That would cause a large vacuum leak.

And that is behind the throttle plate.. That's what Joe was saying. (Not just the plate itself but vac leaks located after the throttle body)

My guess as well

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Matt, if your intake manifold has been off any time recently, check to make sure you didn't pinch the metal support bracket (on the drivers side of the car) between the intake manifold and the gasket. That would cause a large vacuum leak.

Checked the intake and everything's good; seated tightly all the way around. I actually had it off about a month ago when I did all the PCV lines.

Do you have a short vid of the engine running at idle? I'd look at the check valve fitting off the short hose on the end of the intake that feeds the brake booster. The end cap can crack & present a large vacuum leak, that you may not actually hear. It;'s that long plastic fitting in your pic that your boost vac line is running close to.

Checked that plastic fitting, also pulled the vacuum line off that comes out of the top of the middle of the intake and checked that and no leaks. I sprayed all the vacuum lines I could find with starting fluid and no leaks were present. Visually inspected all the lines and couldn't find anything that was obviously wrong. Also checked all the intercooler plumbing and fittings and everything's tight. The hoses are mushy, but I can't see anything that would be an obvious leak. This is the second time I've checked all these things too, I actually looked them over when I did the trans as well and replaced what looked crappy.

I think I might go out there right now, pull that T off where I connected the boost gauge and see if I can suck more than 9 psi; I wonder if I have a bad gauge?? I have a vacuum gauge at work; should've brought that home.

Just for the sake of knowing... There's a plastic vacuum line that ties in near the radiator at some electrical/vacuum thing, then runs under the transmission and over to the passenger side of the car. From there it looks like it goes into the car's cabin under the passenger seat. What's this line for?

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