Maf only hesitation
04-13-2015, 09:55 PM
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Maf only hesitation LTFTs are good up to 5000hz. From there they go 10.8 10.5 13.3 16.8 and so on...... I am stumped???? AFR's go up to 18. Runs good in SD. All trims are great as well as wot. I have to agree it does run better with the MAF, hence, why I am trying to figure it out. Any help will be greatly appreciated. Running a Duralast MAF
P.S.
Still learning how to tune. Have a log for yall to see.
P.S.
Still learning how to tune. Have a log for yall to see.
Last edited by mrvedit; 04-14-2015 at 09:08 AM. Reason: Fix formatting
04-19-2015, 12:47 PM
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It's basically a stock tune setup for tuning the MAF. I tell it to keep adding fuel but does nothing. I am leaning towards the ecm, but don't know for sure. I've added up to 50% and the trims are still the same.
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04-21-2015, 07:07 PM
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The MAF is a slow instrument. That's why it is ignored at
unsteady-MAP conditions (i.e. fast changing air mass flow).
It's very likely that an air-step will be giving you a lagging
air mass reading and a transient lean fueling. That would
lead to KR (at best) which always makes for some hesitation.
But this will not affect LTFTs which are steady state
average based. You can have good steady-pedal trims and
mixture from MAF-only, but you probably can't fix the lag.
On the other hand maybe a slow spooling turbo is enough
to cover the MAF reading lag (I'd bet not, though).
unsteady-MAP conditions (i.e. fast changing air mass flow).
It's very likely that an air-step will be giving you a lagging
air mass reading and a transient lean fueling. That would
lead to KR (at best) which always makes for some hesitation.
But this will not affect LTFTs which are steady state
average based. You can have good steady-pedal trims and
mixture from MAF-only, but you probably can't fix the lag.
On the other hand maybe a slow spooling turbo is enough
to cover the MAF reading lag (I'd bet not, though).
Took it to a shop in Houston and they found out that the MAF was only reading up to 6000hz and would stop. Fixed problem with an ls7 MAF. 
04-26-2015, 11:47 AM
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LSX, what oe MAF do tuners like to tune the most I'm going from stock 78 to a zo6 or truck MAF with pigtail I guess wanted to know which one is easiest to deal with
04-26-2015, 12:23 PM
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Z06 and truck MAF are the same (at least through the mid-'00s)
body but I have found that the truck -table- fit a low-mods
setup and the Z06 table, a H/C/I/E setup better as far as
AFR fidelity went (fuel side being left stock). This using the
same descreened 85mm truck MAF hardware.
Numerous tables out there varying in detail, but this pertains
to the platform and not the piece.
body but I have found that the truck -table- fit a low-mods
setup and the Z06 table, a H/C/I/E setup better as far as
AFR fidelity went (fuel side being left stock). This using the
same descreened 85mm truck MAF hardware.
Numerous tables out there varying in detail, but this pertains
to the platform and not the piece.