PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

going into OL when mashing gas

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Old Jan 15, 2007 | 06:48 PM
  #1  
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From: Longwood
Default going into OL when mashing gas

just started scaning with efi-live, and noticed that for whatever reason when i mash the gas from a roll it goes from closed loop to open loop in driving conditions.

Here is what im dealing with:

Frame - 2820
rpm - 722
TPS = 10%
MAF = 7.01 lbs/min
MAP = 10.03 hg
spark advance - 25
Duty cycle - 3%
Long terms - -12.5%
Fuel status - CL

Then the next frame

Frame - 2821
rpm - 897
TPS = 54%
MAF = 5.24 lbs/min
MAP = 30.1 hg
spark advance - 8
Duty cycle - 17%
Long terms - 0%
Fuel status - OL-drive

The one thing that i think stands out is that the maf goes gets lower and the MAP gets real high...

And from some searching ive found that some people had this problem cause of tps voltage going too high from ported tb but i checked voltage and from 0-100%tps my voltage is 0.5-4.3, hitting 100% at 4.0 tps voltage

Any help here would be greatly appreciated.

O on second thought, would this be because of turbulance in airflow?
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Old Jan 15, 2007 | 08:15 PM
  #2  
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From: East Central Florida
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The MAF dropping rather than rising is peculiar but everything
else seems sort of right. You might look at the MAF table and
see if there is anything abnormal there, which might translate
a rising frequency into a falling airflow. Perhaps log MAF freq
as well as the reported airflow number.
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Old Jan 15, 2007 | 09:00 PM
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From: Longwood
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this is gona seem funny... but for whatever reason my maf freqs were tuned way higher then the stock figures. for example at 1500 it was 0.3 on stock and my current tune was 0.7... soo im thinking that was the reason, but im gona scan some tomorow night and make sure that it doesnt go into OL.

Thanks for the help.
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Old Jan 15, 2007 | 09:12 PM
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You seem to be concerned about the open loop thing you say when you mash the gas. You are probably exceeding the TPS% that triggers PE mode although at the rpm you posted, the stock PE enable table would be at 64%. Has that table been changed from stock?
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Old Jan 15, 2007 | 09:58 PM
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From: Longwood
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wow... thats it... i cant believe i didnt remember messing with that but yea it was changed to 50%...

Thanks much for the help, ill verify it tomorow night, thanks!
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