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Odd MAF reading...

Old 06-26-2011, 12:52 AM
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Question Odd MAF reading...

I have a basically stock LS1 with a Procharger. I trying to diagnose a low boost issue and am also getting some odd reading at my MAF. Does anyone have what kind of reading you get with a FI car at idle and at 2000 RPM?

My MAF reading at idle is 3g/s and 10g/s at 2,000 RPM. When we took the tubes off the Procharger air box the readings rose to 6g/s at idle and 18g/s at 2,000 RPM. Another interesting reading was with the O2 sensors; they would stay at 0.8-1.0.
Old 06-28-2011, 05:03 PM
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Anyone?
Old 06-29-2011, 08:11 AM
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MAF's and FI dont mix on all but the newest platforms due to hardcoded internal limits of the ECU.

Other than that, your airflow readings are way small. Because of the aforementioned limit, some hacks resort to 'scaling' injector settings, so all airflow, airmass, and the respective fuel flow figures are all gonna read (hopefully proportionally!) low.

I don't know what you mean by 'the tubes', but if you mean disconnecting the MAF, and falling back onto unscaled SD, then yea, your readings would probably go back to normal where and 6g/sec idle and 18g/sec low rpm cruise sound perfectly reasonable.

Welcome to the land of the hacks
Old 06-29-2011, 10:03 AM
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850rpm idle 11g/sec on my car.
Old 07-03-2011, 01:00 PM
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RedHardSupra - I didn't disconnect the MAF. I disconnected the charge pipe from the procharger. This way I can see what the MAF read with the procharger attached compared to the motor just running on open air.

amazonic - Thanks. But is this with any sort of FI or stock?
Old 07-03-2011, 01:29 PM
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its with a p1sc
Old 07-03-2011, 08:38 PM
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Yeah mine with a P1SC-1 is 10 idle and around 30 @2K
Old 07-07-2011, 01:03 AM
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flame - Thanks again for your assistance.

I vented my BPV to atmosphere. Also added a breather cap to the oil filter. I still have to mess around with the rest of the PCV setup.

Anyways, I plugged it into my computer and my MAF readings did rise a little bit. Today I was getting 4.5g/s at idle (650rpm)... but yet again I am still getting 10-11g/s at 2,000rpms. My air temp reading was around ~109 degree's. Also after a quick run my boost was ~5psi. So it appears I managed to get a little more air at idle, otherwise no other changes .

Next I will remove the BPV and block off the outlet.
Old 09-13-2011, 05:48 PM
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Originally Posted by MadIceV8
Next I will remove the BPV and block off the outlet.
Finally got my head unit back from procharger showing that nothing was wrong with it. Tried what I mentioned above with no improvement.
Old 03-04-2012, 02:41 PM
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Bump for anyone else with idea's. Spring is starting to come up so I will be taking the car out of storage and messing with it again come April.


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