will put a bigger spring in the bov, thanks. 
idle and PCV question
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idle and PCV question Hi!
Just finished my LM7 turbo build and getting into the tuning with MS3. On idle the Engine MAP reads 90 - 95 kPA, is this normal for a turbo engine? Also it runs kinda rich with a Denmah base tune. Also the BOV is open on idle, is this normal too?
Can the high MAP be a result of my PCV system? See attached image.
Just finished my LM7 turbo build and getting into the tuning with MS3. On idle the Engine MAP reads 90 - 95 kPA, is this normal for a turbo engine? Also it runs kinda rich with a Denmah base tune. Also the BOV is open on idle, is this normal too?
Can the high MAP be a result of my PCV system? See attached image.
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The map sensor is def off, unless you have one hell of a vac. leak, but then the blow off valve prob wouldn't be open-yes the blow off valve should be open at idle and cruise, WOT u lose vac, and it shuts
More than likely its rich because the false map sensor reading has the engine thinking it has a higher RPM and wants more fuel.
Do you have a vac gauge, throw it on there and ck vac.
The PCV can throw it off, but usually when change things around on an already tuned engine, mine did that when I switched up the system, I had to retune it at idle (Holley HP)
More than likely its rich because the false map sensor reading has the engine thinking it has a higher RPM and wants more fuel.
Do you have a vac gauge, throw it on there and ck vac.
The PCV can throw it off, but usually when change things around on an already tuned engine, mine did that when I switched up the system, I had to retune it at idle (Holley HP)
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From: Bowling Green KY
You probably have a mismatch between your MAP sensor, and what the ECM thinks you are using. If you had a 1 bar sensor in the manifold, and the computer thought it was a 2.5 or 3 bar sensor, you'd get some type of a reading like that. The map sensor as I understanding puts out 0 at complete vacuum and 5V at full scale. If you had a 1 bar sensor and were about 40 kPA it would put out about 2 volts. If your ECM seen 2v from the sensor, and thought it was a reading from a 3 bar sensor it would think it was 120 kPA.
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You probably have a mismatch between your MAP sensor, and what the ECM thinks you are using. If you had a 1 bar sensor in the manifold, and the computer thought it was a 2.5 or 3 bar sensor, you'd get some type of a reading like that. The map sensor as I understanding puts out 0 at complete vacuum and 5V at full scale. If you had a 1 bar sensor and were about 40 kPA it would put out about 2 volts. If your ECM seen 2v from the sensor, and thought it was a reading from a 3 bar sensor it would think it was 120 kPA.
In MS3 I selected the GM 3bar, I got one from EFI Source (3bar), maybe thats the problem...
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Found the problem, the 3 bar MAP sensor is not working. I checked the vacuum and it was good Replacing the 3 bar MAP sensor for the original 1 bar I get the correct readings. On idle between 30 - 40 kPA.
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