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Boost gauge reads 0 vacuum

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Old Mar 16, 2024 | 09:36 PM
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Default Boost gauge reads 0 vacuum

Hello this is my first post so let me know if I’m in the wrong place

I have a 1992 MX-5 with a CXracing turbo kit and a Megasquirt PNP ECU

the problem I’m having is my boost gauge never going into vacuum I smoke tested the engine and there are no leaks and my tuner said to get a better tune he needs to be able to tune vacuum but he can’t because I’m not getting any (my tune right now is a little rough engine bogs until it’s warm then when I drive it around for a while and I go into neutral the rpm drop to below 500 and sometimes stalls the car)

any suggestions help, I am desperate
Old Mar 16, 2024 | 10:16 PM
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Bet you hired that guy who charges $300 for remotes.

Step 1, fire your tooner.
Step 2, hire a real tuner.

You don't tune using a boost gauge. You tune with map. Use tuner studio to see if your map sensor is reading vac.
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Old Mar 16, 2024 | 11:01 PM
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Is your MAP sensor not connected to the manifold or is somebody running a scam on your ignorance?

cheaping out on a turbo kit and ecu just to pay a "tuner" that appears to be misleading you is a weird way to go about things.
Old Mar 17, 2024 | 02:55 AM
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If you have a line going to your map sensor, make sure it isnt pinched somewhere, maybe where it's going through the fire wall
Old Mar 17, 2024 | 11:40 AM
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Thank you all for your advide and my tuner is my buddy and I trust him he does not charge me he knows what he is talking about and I don’t so I’m sorry if I relayed his message wrong 😅
Old Mar 17, 2024 | 02:07 PM
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Cool, that changes things. Please understand that since COVID a bunch of remote "tuners" have popped up who charge for services they are totally unqualified to provide. It isn't quite as bad as the people who continue to install rx-8 yellows, but it is close.

The advice you have been given thus far is still valid as your starting point. Check TS to confirm your map isn't reading vac, and if it isn't, troubleshoot. The most common issue is a blocked signal line.
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Old Mar 18, 2024 | 04:21 AM
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Originally Posted by Ted75zcar
The most common issue is a blocked signal line.
This, sometimes people dont cut the grommet properly and that's where its squeezed
Old Mar 18, 2024 | 12:21 PM
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Post a picture of where your boost/ Vacuum reference line is attached to the engine.
Old Mar 18, 2024 | 08:52 PM
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Originally Posted by Ted75zcar
Bet you hired that guy who charges $300 for remotes.

Step 1, fire your tooner.
Step 2, hire a real tuner.

You don't tune using a boost gauge. You tune with map. Use tuner studio to see if your map sensor is reading vac.
So just started researching remote tunes/tuners.......what is going rate? How much expect to pay for competent tuner and not having to go the Dyno route?

Last edited by 2Zooms!; Mar 19, 2024 at 06:11 PM.
Old Mar 19, 2024 | 05:17 AM
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Sounds like the other end of the hose connected to your MAP sensor/ECU is connected to the piping before the throttle body. I.e in the intake pipe between the intercooler and throttle body. Thats one way you'll only see boost and near to no vacuum.
It needs to be connected to the intake manifold to read both vacuum and boost.
Post a photo of your engine bay.
Old Mar 19, 2024 | 06:32 PM
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Can you post videos on here?
Old Mar 19, 2024 | 06:34 PM
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I will get a picture of my engine bay when I get home
Old Mar 19, 2024 | 07:24 PM
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Just engine bay

Where the tube goes from my ecu (MAP) to the engine

Close up
Old Mar 19, 2024 | 07:25 PM
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Let me know if this helps I can easily take more
Old Mar 19, 2024 | 08:10 PM
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Why using that port and not the blank easily accessible one that used to go to purge?
Where is IACV on throttle body connected now? Or is it a T?
Old Mar 25, 2024 | 08:47 PM
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Default SOLVED!

I found my vaccum leaks
my problem was when I smoke tested it I did not block the intake on the turbo so all the smoke was escaping there and not building pressure to escape from other places

still need to do the repairs fuel rail gaskets
Thank you everyone for your help
Case Closed
Old Mar 27, 2024 | 11:31 AM
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What was causing your leaks?
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