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Old 08-28-2014, 09:56 PM   #1
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Default Low Vacuum and Rich Idle

Currently at Idle I am seeing -9 vacuum and idle search. Once warm the idle search stops and my AFR's at idle are 10-10.1 rich. Low vacuum continues. Runs 5psi boost fine with good AFR's. Rich at the top RPM Range (5-6k).

Turbo Setup:
5 pounds of boost
EMB piggy back
Maf still connected
Walboro pump
Stock injectors
COPS setup
External Wastegate w/ TIAL BOV
PCV removed/vented and gasket cover to air, intake side plugged (Don't know why)
Intake at turbo/filter plugged, gasket cover to air (Again don't know)

Things tried:
Hooking pcv valve and turbo side intake back up to gasket cover (no change)
Checked over and over for vacuum leaks (carb cleaner, checked connections)
Cleaned MAF

Things haven't done:
Checked injectors for leak/seal (took injectors out and cleaned previously)
Installed a Megasquirt
Replaced stock o2/ wideband o2
Bypassing FPR

I am looking to get the Vacuum in line and understand or fix the rich idle. Seems like they could be related but may be way off base. Any help would be much appreciated. I was not the original engineer of this turbo setup. Thanks in advance.

Last edited by Test Subject; 09-01-2014 at 10:53 PM. Reason: Updating info
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Old 09-21-2014, 12:48 PM   #2
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Old 09-21-2014, 03:04 PM   #3
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Your off the chart AFR is not helping. Do you not have control over your fuel at idle?

-Have you done a simple compression test?
-Have you simply tried pinching vacuum reference lines? BOV, Wastegate, FPR, Brake Booster
-Have you checked your timing? A tooth off will cause this. I see it all the time when someone thinks they have their timing set properly only to post a picture and it's off. The BP motors are a bit tricky if you aren't looking at it just right.
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