Fuel Distributor Differences between CIS-E('85-87 4kq 5 cyl K X) & CIS-EIII(post '87 5cyl NG)

[Ben Swann]

OK - I think I understand.  There may be differences internally with slit
size, valving, etc too.    It would seem that the wider range of actuator
current provided in CIS-E3 would give better control - the actuators are
the same.  Don't know about the Airflow position sensor pot.

Though it would probably work putting the CIS-E3 distributor on the CIS-E
airflow plate, or even leaving with the CIS-E setup, it's probably best I
locate a complete CIS-E3 airflow/distributor combo.  Off to the not so
local parts recyling center.

One alternative I have by chance.  It appears I picked up a 100 Airbox with
throttle plate and distributor.  I suppose I could combine the appropriate
pieces from that.

It seems Bosch Fuel Injection & Engine Management by the late Probst is one
book tha must be read over and over.

Thanks for the replies.

Ben

On Wednesday, February 13, 2002 8:17 PM, Dupree, Jim
[SMTP:dupree at alldata.com] wrote:
> They are different! The CIS-E III system is what Audi referred to as
'High
> pressure concept'. The fuel pressures in the system went up
significantly.
> The system pressure jumped to 6.1 - 6.5 bar (88.5 - 94psi), CIS-E was 5.2
-
> 5.6 bar (75 - 82 psi). The fuel line connections are different and the
> injectors are also different in their pressure range and threaded
fittings.
> You are stuck using the CIS-E III system complete.
> You may even have mixture problems with the CIS-E III fuel distributor on
> the CIS-E airflow sensor housing. I don't know this for sure but I ran
> across a VW rabbit that had a slightly different housing and it ran way
too
> rich except at idle. The diameter of the airflow sensor plate and the
taper
> of the cone in the housing affect how high and how fast the sensor plate
> lifts for a given air flow. These have to match the fuel distributor
> characteristics.
> I have my own 2.3L transplant under way for my 4kq and I am planning on
> using the complete system from the fuel line connections (supply and
return)
> in the engine compartment all the way to the injectors. I also have a
> complete (almost) donor car. And as I was looking up the fuel pressures
for
> the e-mail I realized I probable have to swap the fuel pumps as well. I
> don't know if the 4kq pump can handle the higher system pressure long
term.
> Too bad the pump is not very old :(
> Good luck and keep us up to date.
>
> Jim
>
>  -----Original Message-----
> From: 	Huw Powell [mailto:audi at mediaone.net]
> Sent:	Wednesday, February 13, 2002 4:41 PM
> To:	bswann at worldnet.att.net
> Cc:	'quattro at audifans.com'
> Subject:	Re: Fuel Distributor Differences between CIS-E('85-87 4kq 5
> cyl KX) &  CIS-EIII(post '87 5cyl NG)
>
> My "gut" is the same on that.  According to Probst, as I recall, CISE
> and E3 are identical fueling systems, the E3 incorporates the knock
> sensing ignition system as part of the engine management - and it is
> usually a separate, stand alone module on these engines anyway.
>
> There is a slight difference, which makes mix and matching components
> *within* the systems iffy - the E3 control pressure reg. is set up to
> vary around 0 mA, versus the E at 10 mA.  This provides, I suppose, a
> better "limp home" mode, but does mean that the computer and at least
> the CPR are different.
>
> If I were you I'd use the "already in the car" system, tack on the NG
> fuel lines if you have the two piece manifold, and hook up the E3
> ignition system at the same time.
>
> The only interface between the fuel & ignition systems on CISE3 seemed
> to be one that allowed the ignition system to pass along the "full
> retard" signal to the fuel computer so it could display a warning light
> on the OBD thing, when Marc and I were trying to figure it out.
>
> Another note, is that when I dismantled my wrecked 90Q for storage, the
> ignition system did come out as a discrete system.  Along with about 12
> other harnesses... an entire 2 cu ft box full of wiring!
>
> Ben Swann wrote:
> >
> > Today's question: Regarding the install of complete NG  setup into
4000Q -
> >
> > Are there any differences I should be concerned about between the CIS-E
on
> > a '85 4000 Quattro and the NG CIS-E setup - in this case from a 87.5 GT
> > Coupe?  I have both, but they appear identical.  I'd hate to go through
> the
> > trouble of swapping the fuel distributor head if there is no
difference.
> >
> > The fuel distributor came with the NG engine but I didn't get anything
> > below that, so I'd have to swap with the airflow sensor plate assembly
> > below on the 4000 if I need to.  Id hate to take apart any more than
> > necessary, however and my gut tells me these are the same - they look
> > identical.
>
> --
> Huw Powell
>
> http://www.humanspeakers.com/audi/
>
> http://www.humanthoughts.org/