ALFAGTV6.COM

Hello,

The mechanic I use says the AFM on my stock(ish) 2.5 GTV6 is running out of adjustment and is now just about 1.5% CO with the air screw all the way out.

It is time to start looking for another one. I seem to remember that the AFMs from other L Jet cars will fit.

Which ones are best and is there any advantage in getting a bigger one on a car like mine, (standard cams and just a skimmed head, CSC manifold and exhaust and a K&N element)?

Thank you

Simon

bmw 3,5l (635) ones should do the trick

Thank you,
Anyone know the part number for one of those?

If you use the BMW afm you also have to modify the airbox as the air flap is larger . With your mods I would not change to another type but source a better condition one instead . Check with Alex as he has huge amount of spares .

here is a new one

http://www.ebay.de/itm/Luftmengenmesser ... 20eb64df8e

or just search by the bosch number 0280202013

Easiest correction to do is to set the CO adjustment screw mid-trave, then tighten the clockspring 1-2 teeth and re-measure %CO. What you see is a normal weakening of the clockspring over time. If your existing afm size was adequate for ~235hp in the old GpA cars it should be enough for any road-going 2.5V6.
Jim K.

Thank you Jim! Yes I didn't think I needed to go up a size, just source a working one. Thank you for the tip. Simon

Latest update on this is that the mechanic had already tightened the spring, he says the problem is a worn potentiometer track. I guess I do need a new one

There's a cheap-ass fix for this one. If you loosen the 3 screws holding the pcb plate, you can move it by just a few tenths of a millimeter, so that a new section of the potentiometer track is exposed. If this is not enough and you want to do an even better job, you can remove the plate, file the fixing holes so that the plate can sit in a new position, exposing a 'new' potentiometer track. On reassembly, be careful not to reposition the wiper too low on the shaft; you want to have the least possible pressure on the track from the spring contact so they both last as long as possible.
Jim K.