Mass Air Flow Meter Question

I had to replace one here in the UK, the price was nearer your $300 than $150 from an authorused F dealer. Lots of rough idling and a check light before I replaced it.

 

majority of 360 owners all have the same concern,i have not herd of anyone doing a 100% fix for this concern,please keep us posted.

 

There is a guy on Ebay selling the MAF's.
http://cgi.ebay.com/ebaymotors/Ferrari-360-Modena-AIR-flow-meter-mass-air-430-355-_W0QQcmdZViewItemQQhashZitem27b68eb999QQitemZ170566531481QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

 

On all Bosch Motoronic systems unless specifically altered by the manufacturer you will experience a fallback if you unplug the MAF. AFAIK this includes the Me7.3. It will default to a preprogrammed map which will yield an ignition retard of between 6-8 deg and an overall enrichment of varying degrees depending on if other system sensors are failed or not. If your IAT is also faulty you will see the same result. However if either were seriously faulty you should also expect a CEL.

Let me pause for a moment to chuckle as I live in Buffalo and I had to laugh when you said it was cold in Vegas. LOL!

If you have the tools, I'd find the measuring block for each IAT and plot them as a function of temperature. Sorry, I don't know them off the top of my head. For grins I'd do the same for the MAF, although I would suspect the IAT before the MAF actually. The temp of the MAF is regualted by a stable current supply and that should be independent of ambuient air temperature. The IAT output however is directly coupled to ambient air temp.

Start there before replacing the MAF's.

 

Oh and I was also just thinking along the lines of temperature. You should also check the coolant termp sensor. Although it should also throw a CEL on "new" Motronic's. I don't have a schematic handy, but it also will cause rough idling especially in the margin temperature area. Whereas if it's really cold (not Veags) or really hot (like Vegas) then it behaves normally. But in the area where the switch thinks it should or might open, then it gets ragged with some of the built in hysteresis inherent in them. The same applies to the IAT.

Sorry for rambling.

Hope this helps.

 

Rather than just replacing parts, it is very easy to hook a diagnostic scanner - even a basic OBD-II scanner to your car and see if the air temperature that is read from the MAF via the DME matches (within some reasonable variation) "reality".

You could also get a similar car and warm them both up and see the reading for air mass at idle to see if the MAFs are reading the air properly.

Cold start problems sound like programming/calibration issues as much as defective parts.

Jim

 

very well could be that the maf sensors are damaged due to oil contaminating the wire. this usually happens when someone overfills the dry sump and oil vapors get drawn in the by intake manifold and then circulate through the air.

If you know of anyone around you that you could swap maf sensors without buying new ones to see if the problem still occurs would be the easiest and cheapest way to isolate your problem.

 

i have swapped mine with other mafs and same thing .i was told it could be a software concern there might be a reflash,im thinking its all fuel related because when i crank for a few seconds turn car off than restart it starts up perfect.

 

There's some interesting compatability info listed on this page regarding MAFs:

http://www.ignitioncarparts.co.uk/PartDetails.aspx?s_pc=PDAFS048%20BA&s_vid

EDIT: the part listed is the sensor only so I would assume you need to already have the casing.

 

Delta, did you check that the DME is in open loop at startup? This can be easily monitored with any kind of OBD diagnostic tool. To get the cats hot faster, the DME should be in open loop and not closed loop. I was thinking also about a failure of the header air injection system but the F430 doesn't have it (the Scud and 360 does have it though).