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Mainly talking about vs-vy v6 tuning & when I got my software I was told not to touch the maf tables as there a calibrated instrument & if the fuel lines were out don't adjust the maf adjust the fuel trim multiplier table!

Now contrary to this the software also said the maf can go out due to oil, dirt or even if the air filter is change or a pod filter put on!

So my thoughts are which is the more accurate way of adjusting the fuel lines when not in AE or PE mode, by the maf frequencies or by the fuel multiplier table?

you could do either but it depends on where your inaccuracy is coming from. MAF transfer can be tricky on delco depending on which codebase you use due to the multiplier/factor method of storing the data, also ensure the end of one table is the same as the start of the next. tuning the MAF also affects torque calculation which and also load axis of your tables. An extreme case would be if you changed injectors or fuel pressure and decided to adjust the MAF table instead of your injector rate your lookup axis on your spark tables would be all off and you'd have to remap your spark table completely.

The injector multiplier table is exactly that, its a multiplication of the injector time referenced to engine speed cylair (mg/cyl).

OK now to the question, I would start by cleaning the MAF if its likely to be dirty, then use the injector multiplier if its there. Only change the MAF if it is a different MAF or if there isnt a injector multiplier table. One thing ive noticed is that neither HPT or EFILive have an injector multiplier table mapped, not sure if its because it doesnt exist or because no one wants it.

if you havn't changed the MAF or it's location then you dont need to adjust it, i only ever adjusted the maf values because there was no fuel tuning on some xdf's, on the $51 i use the Open loop air to fuel ratio vs cylair50 & rpm to adjust fueling which should prob read something like injector delta vs cylair & rpm or something

Cool guys, yeah I sorta know all those ideas & opinion's but I was just throwing it out there to see what most people did & get there thoughts!

So All good keep em coming, it's surprising 1 I had on the dyno a few weeks ago had really lean AFR on load runs & then cleaned the maf & went from around 14.5 Afr on load line down to 12.7 & gained around 7rwKw's!

What does everyone find the best to clean maf's with, I've heard carby cleaner, electrical contact cleaner or of course there is now the proper stuff from crc mass air flow sensor cleaner but it's fairly pricey compared to other options!

electrical contact cleaner here sometimes i use a cottonbud as well if i have time to be carefull.

personally i've only used the CO Contact cleaner or Electra Clean stuff, i have also heard (and im not sure how accurate it is) that using certain stuff can cause issues, eg. some throttle bodys come with a clean coat of something on them and if you use throttle body cleaner it eats this off and puts everything out of whack ....

I’m not sure what to adjust with fuelling for maf, at idle it’s in closed loop so obviously commanding 14.7 but it’s actually seeing 14.4 on the wideband & the stft’s on both banks are negative(-1 to -3) & ltft’s are 0 to -1. Because the trims aren’t far off & then when under load on the dyno it’s commanding 11.6-11.7 but it’s actually seeing on the wideband 12.4 so because it’s opposite on different scales should I be adjusting the open loop afr table so it’s trying to command 0.3 leaner at low rpm & mgc & then almost 1 afr richer on the top end of the scale(hi rpm & high load) or can the maf be calibrated to go opposite on both/separate scales?

your not confusing closed loop idle with closed loop fuelling are you ?

i will only go into closed loop at 14.7 commanded, if its commanding 14.4 it shouldn't be closed loop!

no it's commanding 14.7(in the tp5 log) but it's actually reading 14.4 at idle & then seems to get richer the longer it idles after 10 mins idle goes down to 14.0

But then when looking at what is commanded in the logs on the dyno run it's commanding around 11.7 for a given point but at that actual point on the dyno wideband it was 12.4?