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Missfires in MAF mode

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Old 05-16-2009, 02:16 AM
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Default Missfires in MAF mode

I get constant missfires down low (1000-2000 rpms) in maf mode.

I have an slp maf, cleaned it not too long ago.

When the MAF is disabled I get none. It appears to be reading correctly, it gives hz readings properly correlating to airflow. I got a good ve table and generated my maf table with 3rd order polynomial off of dynamic airflow.

I tried doing wb a/f corrections on top of that and still didnt solve it.

What is going on?
Old 05-22-2009, 02:37 AM
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Bump, my cars running very well and the fueling appears to be spot on but I still get missfires constantly in maf mode. What is the deal? The computer seems to pick up on em but the car is running fine. What can I do?
Old 05-22-2009, 07:13 AM
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Raise the misfire thresholds until they go away and add another 10%
Old 05-22-2009, 10:11 PM
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Where are misfire thresholds located in hptuners? I cant seem to find it.

I tried that one method where you max out a misfire table to 36566 or whatever and that didn't resolve the misfires or the code. I did idle and the other areas on these tables.
Old 05-23-2009, 02:24 AM
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Originally Posted by pHEnomIC
Where are misfire thresholds located in hptuners? I cant seem to find it.

I tried that one method where you max out a misfire table to 36566 or whatever and that didn't resolve the misfires or the code. I did idle and the other areas on these tables.
that's the right place; you must have missed a table there
Old 05-28-2009, 12:37 AM
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Is there any way to see misfires when you delete the maf and go speed density?




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