Fuel Pump Relay differences (between CIS-E and CIS-E3)

[Ben Swann]

Huw you are correct about a soft rev. limit on CIS-E3 - The system increases
Diff. Pressure at 6600 RPM to reduce power, but that is not it.

I took a look at the relays again.  Although the circuit diagram shows the
relay uses the same pins, the location of the pins was changed.  If you lay
the different relays with pins facing up, the location of the pin for the
ignition trigger was changed to the other side.  I will have to move pins on
the relay, or move pin locations on the fuse panel, swap wires or make an
adaptor to make it work.  Make an adaptor may be the best thing, as then
I'll be able to use normal 4kq relays if I don't need diagnostics.

I suppose I can always make the connection inside the car, too or a
pushbutton switch.  From the diagrams I have seen, if I connect the wire for
pin 3 on the Knock sensor unit to ground, that is the same as what happens
when the fuse is inserted in the top of the relay.   I'd appreciate any
confirmmation that this is what I need to do to trigger diagnostics.

I wired a check engine light into the appropriate place in the instrument
cluster.  It does go on momentarily when the engine is started, so that is
good.

Ben
----- Original Message ----- 
From: "Huw Powell" <audi at humanspeakers.com>
To: "Ben Swann" <benswann at comcast.net>
Cc: <quattro at audifans.com>
Sent: Wednesday, February 04, 2004 9:11 PM
Subject: Re: Fuel Pump Relay differences


> > I am trying to find out why the fuel pump relay for '87.5 GT
> > coupe/CIS-EIII or similar from 5ktq will not work in the '87 4kq that
> > I have transplanted the NG and CIS-EIII wiring harness.
>
> If I recall correctly, the CISE3 system runs the overrev protection from
> the ECU; in CISE it is done at the fuel pump relay.
>
> Just an idea you might be able to use to help you figure it out by
> tracking wires on the diagram carefully.
>
> Perhaps the coil signal wire's place on the early version is replaced by
> something from the ECU on the later one, and that isn't there on your
> project car.
>
> Hoping this might help...
>
> -- 
> Huw Powell
>
> http://www.humanspeakers.com/audi
>
> http://www.humanthoughts.org/