Bad EGR?

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Mar 17, 2016 | 04:30 PM

#21

VikingTrad3r

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yes. wherebh first put the camera in the bid there is a huge sucking hissing sound. maybe its pressure coming out? maybe its air sucked in. check alllll those vac hoses that are right there. u might have a crack or tear in the rubber boot. also the throttle body gasket/and hinge loints. and check the exhaust gasket you fixed.

Quote:

Originally Posted by 9T3VETTE

From your video there is clearly a leak somewhere. It sounds like a manifold gasket to me. Have you checked all around the exhaust manifold gasket with a rubber hose to your ear?

Do you still have the AIR system and is it working properly? It's possible the diverter valve is not working properly introducing fresh air into the system.

Mar 22, 2016 | 08:38 PM

#22

1993C4LT1

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Well took my car to a corvette specialists shop. If they can't find anything wrong, I don't pay anything. Dropped it off last Saturday. Called today, owner couldn't find anything wrong

. Told me to give him one more day to see. Let's hope they find the issue.

Mar 24, 2016 | 05:09 PM

#23

1993C4LT1

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Well they couldn't find the culprit. I'll figure it out one day. I searched for people that had almost same problems as me, with no updated results. I'll see if there's anything in the FSM that mentions what will cause the IAC to be at zero with a warmed up engine. I'm hoping that by fixing that, it will make the car less lean.

Mar 24, 2016 | 09:02 PM

#24

1993C4LT1

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Does anyone see a point in hooking up a vacuum gauge?

Mar 27, 2016 | 09:07 PM

#25

93Rubie

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Won't hurt. IAC at zero means it is shut. Your getting air somewhere. Do you have a scan tool of some sort?

Last edited by 93Rubie; Mar 27, 2016 at 09:08 PM.

Mar 27, 2016 | 09:10 PM

#26

1993C4LT1

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Quote:

Originally Posted by 93Rubie

Won't hurt. IAC at zero means it is shut. Your getting air somewhere. Do you have a scan tool of some sort?

Yes I do. I can pretty much view everything.

Mar 27, 2016 | 09:32 PM

#27

93Rubie

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Any chance seeing a screen shot of it?

Mar 27, 2016 | 09:55 PM

#28

1993C4LT1

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Quote:

Originally Posted by 93Rubie

Any chance seeing a screen shot of it?

Yes. I would email it, but it's a .csv file. I'll post it up tomorrow.

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Mar 28, 2016 | 01:44 PM

#29

1993C4LT1

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Here are some screenshots of datalogs I recorded. I'll get some screen shots today, where you can view everything. This one is part throttle, with AC off

BLM's are perfect at higher speed.

AC on, and both banks lean.

Mar 28, 2016 | 04:52 PM

#30

93Rubie

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Remind me again....do you have any drive-ability issues?

Those are not horrid. Adding fuel at lower speeds yes but nothing crazy.

Lower speeds, typically=less load=less air flow=more likely to be a vacuum leak.

Have you double checked your MAP reading to a vacuum gauge?

Mar 28, 2016 | 06:18 PM

#31

1993C4LT1

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No drivability issues. I can see my MAP reading on my scan tool. Not sure how to check the MAP reading with a vacuum gauge, but I'll find out

Mar 29, 2016 | 07:38 PM

#32

93Rubie

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Watch a few more of my videos I cover it. Its not a direct comparison 10in Hg on the scan tool=20 in Hg in the intake if Barometric pressures 30 in hg.

Mar 29, 2016 | 07:50 PM

#33

pkincy

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With the IAC at zero there is air getting around the TB blades isn't there. Have you pulled the TB, pulled it apart and cleaned it well.

Mar 29, 2016 | 08:34 PM

#34

1993C4LT1

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Quote:

Originally Posted by 93Rubie

Watch a few more of my videos I cover it. Its not a direct comparison 10in Hg on the scan tool=20 in Hg in the intake if Barometric pressures 30 in hg.

Thanks, will do.