DFI, Batch Fire, and other myths

[Shannen Durphey]

Clarence L.Snyder wrote:
> 
> Clarence Wood wrote:
> >
> >   Please give more information on "motor-vac".  How does it work?  How much does it cost?  Where do you get it?
> >
> > Thanks,
> > Clarence
> >
> > At 06:40 PM 1/21/99 -0500, you wrote:
> > (snip)>I don't know if it acts as a sponge or what, but the presence / absence
> > >of carbon on the intake valves makes a SIGNIFICANT difference in
> > >driveability. The 3.0 litre V6 in my aerostar had a BAD stumble off idle
> > >when partly warmed up - to the point that on a cold day if I fired it up
> > >and drove to the corner down the street it would invariably stall when
> > >pulling away unless I floored it. Tried everything. Finally used a
> > >"motor-vac" on it, which does an excellent job of decarbonizing - and
> > >it's been perfect since.
> > >
> > >
> It is a fuel system / engine cleaner unit that connects to the car and
> draws a calibrated amount of fuel into  itself. You add a very
> concentrated cleaner to the gas, which is then tun through the system,
> from the filter forward under pressure. You run the engine through a
> cycle with this beasy connected and the intake valves, cyls, lines, and
> injectors are clean enough you couls eat off of them. I was a doubter
> myself 'till my brother called me and said they needed a guinea pig for
> the distributor to demonstrate the gizmo on - and knowing my AeroScare
> was misbehaving, and he could not fix it.
> Never know it was the same truck.
> The unit is expensive - several thousand if I remember correctly, and my
> brother has not bought one - yet. Apparently they are also "rotunda"
> branded and sold to Ford dealers - and sold under several other brand
> names. About the same size as an antifreeze recycler or bar fridge.

Just to add a little to this, I used to do motor-vacs in the shop I
worked in.  They worked great, but recommended price was about
$80.00.  They are made by a co. owned by Snap-on.  Anyone interested
can search on the web, there's a page for them somewhere.

Now for the good stuff...  The special cleaner was similar to GM Top
Engine Cleaner.  So similar that we saved a bundle by switching to
it!  Concetration that seemed to work best was 1/2 can to 5 gals gas. 
Machine was simple 12V pump, tank, mechanically adjustable pressure
regulator, and timer.  So the DIY'ers can easily make one!  Hardest
part is making hoses to connect to FI system.  If you play your cards
right, the whole thing could be done for very little $$.  

Shannen