Info needed on Lucas single-point efi

[Richard Cartledge]

Rich Mauruschat wrote:

> At 15:16 08/07/97 +0100, you wrote:
> >I am looking for any info on the web or books on LUCAS Single-point
> fuel
> >injection.
> >
> >I can find mech abou the BOSCH L-jet on my '86 BMW, but nothing for
> my
> >friends '91 River 820SLi 16v.
> >
> >His car is doing 11mpg, so I want to help him sort this out ASAP.
> >
> >Thanks for any info, Richard
> >
> >
>
> Is your 11mpg accompanied by obviously rich running? May be worth
> checking
> the coolant sensor operation, a common problem with earlier Lucas
> systems;
> the sensor fails showing a falsely low temperature measurement and
> hence
> over rich fuelling.
> Also has power been disconnected from the ECU? The SPi system has an
> 'adaptive' fueling control which adjusts gradually for changes in
> operating
> conditions and engine condition etc. When power is disconnected the
> ECU
> suffers severe amnesia and forgets all it has learnt in one go and
> takes
> time to readjust. This is usually apparent from idle exhaust gas CO
> readings, which default to approx. 6% until reset electronically via
> the
> diagnostic connector (no mechanical adjustment available on SPi).
> As an aside, is the 820SLi actually single point injection? 'i' suffix
>
> models are usually multi-point and 'e' suffix single point but this
> may not
> be universal.

----------------Thanks for the info,  the mixture seems to have no
manual adjustment so I think maybe the temp sensor is faulty, I got
about 200ohms when hot from the sensor.

When the air inlet trunking is removed from the injector bowl, the the
throttle butterfly is awash with fuel even at idle. The car seems to run
OK though.

The battery has probably been flat as the car has just been purchased
from the back of a used car showroom and had probably stood a while.

I don't have a gas analyser, so it would probably be best to have the
mixture set electronically by a professional garage - I'll change the
sensor anyway.

Regards and thanks, Richard