I'm descreening and porting my mass air flow sensor tomorrow and my question is will a tune be necessary? Will it run any richer or leaner without a tune? Will it throw codes?

-Brian

 

i think if you do that, you do need a tune.

i say you leave it alone. i have heard bad things abour porting descrenning.

 

necessary... maybe ... some cars run rich from the factory... MAF ends/descreened MAF lean the car out ... some cars that do run rich from the factory love to run a little leaner...

Other cars you'll get pinging ....

for max effort a tune should be done (even stock cars can gain HP w/a good tune) ... but if you don't get any audible pinging/loss of power ... you can go w/out a tune... you just *may* be down a few ponies...

I would Your best bet IMHO is to either get a tuning suite and learn it... or wait to get a tune until after you do some larger items to the car (engine work, or when you have every bolton) ...

and yes... it will throw codes if it causes it to go so lean that the fuel trims can't correct... (they can correct for part throttle swings of 25% either way ... but closer to 0% correction the better for WOT)

 

Until you can tune for it, you safest bet is to leave it alone

 

Well I have a personal tuner and he has my car tuned just I'm waiting on his wideband to come in and it would be a lot easier for me to just make one stop whenever he gets that in. Instead of going down this weekend for the tune and then next month whenever his wideband comes in.

 

Calibrate your MAF...

 

Yes, if you get your VE table dialed in, then MAF cal is easy.

 

The PCM will compensate up to 25% on the fueling, so it will adjust for a ported MAF no problem.
Driving around with a ported MAF will give you positive Ltrims and ultimately make you run richer at WOT.

If you drive around with a stock MAF, but then switch to the ported MAF at the track right before you make a run, then you will definately run leaner at WOT. This usually shows a power increase and you get your fastest time.

 

Why are you porting the MAF? All this will do is cause it to run lean and could cause low driveability problems. I have tuned cars with the stock MAF that put down well over 600 RWHP.The screen actually helps direct the flow of air into the heat sensors to reduce turbulence..Leave the MAF as is..

 

off topic

 

Then give us a little "write-up"

 

Listening.

 

With HPtuners 2.x, theres a histogram you can load... Basically, leave your maf plugged in, but set the fail to 0 so that your car runs off SD mode. Then load the maf cal histogram in hptuners scanner. It will record the dynamic airflow (based on VE) for each of the cells in the MAF table (based on maf hz.) Its as simple as copying the histogram into the bin and setting the maf fail freq back to stock.

 

I see MAF AFR Error and Commanded AFR?

Which Histogram are you referring to?

When you say set Fail to 0 - you mean modify the .bin, or is this a function you can force from the scanner ?

Thanks for the help.

 

I dont have HPT in front of me, but its one of the presets in HPT 2.x. also, setting fail to 0 is in the .bin, Under engine diagnostics in with the DTS codes.

 

Below is the screen shot of 2.x Let me know which one you mean...thanks for the help

 

I have problems with lean codes 1 and 2 and my maf is ported. It is driving me nuts. Get a little pinging around 3000rpm. Any ideas?

 

you're kidding, right? this is one topic that's been beaten to death, it's documented VERY well, and it has been that way for over a year now.

 

I didn't see that there were more posts to this thread
(...I must have lost the email...?).

VE is dialed in (using OLSD Auto VE Tuning method);
then enable MAF, log MAFREQ and MAF, and use same technique to adjust MAF table.

Or log DYNAIR vs MAFREQ in OLSD.

As GuitsBoy has said above.

Edit: There has been a lot written about this, as RHS said...

 

ya i`m kidding thats why i wasted time to type on this f keyboard.