MAF vs. SD

[Gary Derian]

MAF takes the calculating out of the fuel delivery but you still have to map
ignition timing.  For me, a rpm/mass flow map is less intuitive than an
rpm/vacuum map but that can be overcome with a little thought.

Gary Derian <gderian at oh.verio.com>


> Actually MAF is a much beter method since it takse a lot of calulating out
> to the process, SD converts RPM, MAP, Temperatue into a mass valuem
> (Grams/second). A MAF system measures it directly in g/s.
>
> But... The old GM MAF's are very cheep and prone to failure,. The standard
> "rap on the unit w/screwdriver hande" test would result in eratic MAF
> readings. his usauly happened between 30K and 80K miles.
>
> This is why GM went to SD MY89 - 91/82 in F and Y cars.
> The waranty costs were too high. Finaly they developed a new MAF design
with
> adiquate range in or about 1992 (Y car). The new design has been trouble
> free and meets the OBD II needs.
>
> It is interesing to note that they use MAF and MAP,