Unknown Plug Under Engine Cover?

[Tbird6]

Thank you very much for the detailed pictures!
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[Tbird6]

Plug just laying on the back of the engine! Plugged it back in and good to go.

Only a short test drive but really did not notice much if any power difference?
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[glock-coma]

No power difference, it will just recirculate boost back into the intake air as normal now.  If it can't recirculate or relieve the pressure it will put it back into the turbo and you'll get a "flutter" which is not healthy for them.

http://www.turbosmartusa.com/technical-articles/flutter-compressor-surge/

[Tbird6]

That makes sense but still surprised I had no check engine light and no stored codes I could find?

Oh well it's a least hooked up now!
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