Re: CO way to high

["Melissa & Jim" <jadney@vwtype3.org>]

On  9 Sep 97, Noddaz@aol.com wrote:

> In a message dated 97-09-07 13:29:31 EDT, you write:
> 
> << > Ahhh, but in one revolution of the distributor, each injector
> has
>  > fired twice while each cylinder has fired only once...
> 
>  Nope.  In one revolution of the dist, each FI contact point has
>  opened and closed only once (there is only one lobe on that cam,)
>  so we get only one cycle of each per dist revolution
>   >>
> And when one set of points opens, two injectors fire...

True.  And when the second set of points opens, the second pair of 
injectors fire.  At this point each injector has fired once, and 
that completes one revolution of the dist.  Since the dist. runs at 
half speed, this corresponds to two revolutions of the crank and one 
complete cycle of the engine.

So we have one complete engine "cycle" = two crank revolutions = one 
dist. rotation = 4 ignition sparks = 4 injection pulses (one per 
cylinder.)

I have the impression that you don't simply want to take my word for 
this, so I have attempted to demonstrate how the single firing per 
cylinder follows from the construction of the D-Jetronix components.  
For furthur confirmation I suggest you consult the following:

Volkswagen Official Service Manual
Type 3 Fastback and Squareback 1968-1973
published by Robert Bentley, Cambridge, Mass, 1974
ISBN 0-8376-0057-X / LPV 997 383 / VSQU
page 4/4, second para., not really clear, however.

Bosch Electronically Controlled Gasoline Injection (ECGI)
VW 1600E, VW 411E, VW 412E, VW-Porsche 914
Workshop Manual 28,Robert Bosch Corp, VDT-WRE 761/1 B
Sheet 3, figure 4, this chart really clarifys things, but the source 
is not readily available.

The 1600 Model Volkswagen Owner's Handbook, revised edition
Published by Floyd Clymer, Los Angeles, 1972(?)
page 347, reproduces same chart.

Bosch Fuel Injection & Engine Management
By Charles O. Probst, SAE
published by Robert Bentley, Cambridge, Mass, 1989
ISBN 0-8376-0300-5 / GFIB
See the following quote on page 3/40 under trigger contacts:
"D-Jetronic injectors are triggered in two groups.  Each 4-stroke 
cycle, D-Jetronic fires each group once instead of firing all twice 
as in L, LH, and Motronic systems."

As I am not likely to be around for any of the rest of this 
discussion.  I would appreciate it if someone else from the list 
could step in and offer any additional help if it is needed.

Jim
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       Melissa Kepner                                    Jim Adney
                             Laura Kepner-Adney
                         jadney@vwtype3.org      
                             Madison, Wisconsin
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