Ford MAF

[H. J. Zivnak]

According to Chas. Probst (Ford Fuel Injection and EEC) the vane air flow in
the 1.8L is different from any other Ford VAF sensor in that the output
voltage drops as air flow increases. Voltage should be 4 volts closed, aprox
0.5 volts open. He says this is similar to the early L-Jetronic. The Ford
MAF (up to 93 at least) should output 0.2v idling to 1.5v max, engine
running, or 0.7v key on engine off. Also, the Ford MAF runs on a hot wire
temperature differential of 200 C while the Bosch differential is 100 C and
the hotwire is in a bypass not centrally mounted like the Bosch.
I hope this helps. Joe

-----Original Message-----
From: ABTSZ <ABTSZ at aol.com>
To: diy_efi at efi332.eng.ohio-state.edu <diy_efi at efi332.eng.ohio-state.edu>
Date: Sunday, May 10, 1998 9:32 PM
Subject: Re: Ford MAF


>In a message dated 98-05-04 21:03:14 EDT, you write:
>
><< Attn: Ford Guys
>
>         A friend with a 1994 Escort GT, 1.8 twin cam is looking to do some
> minor modifications.  The MAF is the flapper door style.  It has a 7 pin
> connector.  We pulled the other style MAF off a plain Escort.  It has a 4
> pin connector labled A B C D.  Is there a way to incorporate this less
> restictive MAF into the twin cam Escort setup?  I think they both have the
> same output, just concerned about the scaling.
>         Anyother tips/advice is appreciated.
>
> Paul Tholey
>  >>
>
>Here is a sight with alot of info on Bosch AirFlowMeters (AFMs) I think
they
>are identical to the ones Ford uses.  Actually, I think the Ford units even
>use Bosch parts #s.
>
>http://www.students.tut.fi/~k124775/
>
>The problem is, I can't get thru to the sight at the moment.  I don't know
if
>they are haveing temporary server problems, or are defunct.  But it WAS a
>great sight.
>They had a chart showing the voltage to Air Flow ratio (what you are
looking
>for) although it would be different in different sized AFMs.  The reason
for
>the extra pins (i think) would be the Air temp which is used as a seperate
>factor in the calculation when using AFMs, whereas with MAFs, this is built
in
>to the 0-5v output.  I am pretty sure AFMs also put out 0-5v.
>Anyway, that's all I know (or think I know!)
>
>Adam