MAF Adjustment There is an adjustment screw on each MAF (under a small circular cap cover that is usually blue). Pop the blue caps off of your MAFs (See attached picture). Remove the black data cables to your MAFs. The outermost pins on the MAF interface to the cable, pins #1 and #6, (See attached Picture), write down your ohm-meter resistance value (See Picture on setting of ohm-meter)$5.00 at Harbor Freight. Ferrari sets it initially to 383 Ohms. You probably want to be within +/- 3 ohms, say 380 to 386 ohms on each side. You may need a different value. Your MAFs may be mis-set to different values. Your two MAFs should each have the *same* resistance value, regardless of your setting. Turn the screw beneath the blue caps counter-clockwise to richen your mixture, clockwise lean it. For faster revving of your engine, lean your mixture. For quicker starts and max power, richen your mixture. You can adjust until you get a resistance value that suits you (just make sure both MAFs are set to the same level). Too rich and your engine will be slow to rev, your cats will get too hot, and they will trip a Check Engine light. No big deal, just lean back your mixtures. Too lean and your 348 will take forever to start. 5 "urr, urr" cycles at start is typical. More than that and you're probably too lean. Also, too lean means that your engine, rather than your cats, will be hot, and your power will not be up to full potential. Get the right mixture adjustment and then your 348 will make beautiful music for you. You can do all of this *without* resetting your ECU's, too. Adjust, measure resistance, then start her up. Repeat as needed. Even better if you have a fuel to air ratio meter to more precisely report on your progress. Dont forget to relearn your ECUs. Reset the ECU on a cold engine, by disconnecting the battery for a couple of minutes. Then reconnect the battery, start the engine without using the accelerator and with all electrics off (don't turn anything on-off) and let it idle until the radiator fans come on about 15 to 20 minutes. This info is from No Doubt and Marco Image Unavailable, Please Login
This information is fantastic... Thanks to ND and Marco for the info, and to adsphelan for posting it... it's a keeper. Mike in Kuwait
So more Ohms is leaning it out? And less Ohms is richer? I have added Capiisto exhuast, test pipes and KN filter, would I need to adjust my MAF /AF ration after these mods?
ernie Its incredible youre still here trying to escape the humiliation of running off someone as helpful as Rifledriver. Too bad some will always prefer his 30 years of actual experience caring for Ferraris to your years of what? Being ernie?? LOL!
Rifledriver was overrated. His attitude detracted from his knowledge. Can you point to a single car problem that hasn't been, or can't be, solved now that he's gone?
I would not want to start messing with a/f without having a wideband on the car. That screams danger to me. Furthermore, its not fair to say that a richer a/f will result in more power and faster starts. The car has open loop fuel tables that it runs off of, regardless of MAF calibration so it shouldn't matter what you do to the MAF, the start up should be the same. Also, for a naturally aspirated motor, you should look for a 12.8 to 13.2 a/f ratio at WOT. Richer than that, and you will generally lose power. Leaner than that, and you can start to detonate. Messing with the MAF should really be done with a wideband and a dyno to see if you are helping or hurting things.
Took the 348 to a friends hgouse about 10 miles away. Checked the MAFS and tehyw ere 389 on each side. Adjusted them to 381 and drove home. The car definetly felt better.
Oh this is so funny. I think we need a poll: Who is really responsible for running off rifledriver? I think in honor of Rifledriver, Rob should make an icon we can post that says RTFM! that has the smiley face banging a book For "Read the F***ing Manual"
Ooh, ooh, we need a poll! Who PO-ed rifledriver and sent him away? I vote for anyone who questioned his posts. I really liked that guy - but I'm a cynical bastrd too - although it seemed he has a thin skin when questioned on his opinions further. Many times he could have answered without the attitude and with professional definition (e.g., 'cuz I'm a Ferrari mechanic you moron and I see this all the time!). I'd throw ernie under the bus, but the Brotherhood needs him too much! Nice thread too, I was thinking of dragging out the ohm meter today...
I know, but his Drill Sargeant style probably drove away (pun intended) too many Ferrari newcomers. "What?! You don't know how to check your oil only with the motor hot?! No Soup For You!"
He still here, though be it he's only lurking. I just checked and he last longed in on September the 11. Come out and play Brian you know this place is too addicting. LOL!!!!!
He may be, but I think he logs on to mainly answer PM's from people asking him questions, but I am only guessing.
If nothing else works, you can drill a small hole in the centre, screw-in a longer self tapping screw and pull them out. Then, you can plug the hole with a short self tapping screw.
The pot in the MAF is not connected to the MAF's circuitry so it does not alter the MAF's calibration in any way. It is actually connected to the ECU only - MAF's pin 1 is ground and pin 6 goes to the ECU pin 43. So it is a remote ECU trim.