rover v8 starts & stops straight away !

[phil's landy]

Hi there folks !
Please help !
I have a 3.5 efi hot wire out of a 1991 disco (running well before removal), just fitted into my light weight ,
I have wired up the ecu as per details on this site , now there are 2 earth wires coming out of the loom 1 is black and the other is black with white bands on , when i connect the latter to earth the relay buzz's yet the engine only fires up if this is earthed ,but only runs for a few seconds ,i have wired the 3 bar fuel pump to the purple/white wire and also connected the red/white to starter position , i tried a wire direct to the pump and still engine only goes for a few seconds ,there is also earth at the - side of the coil when the engine runs !
Any ideas welcome !
Cheers Phil

[Coops]

white with black bands sounds like the ecu trigger wire that goes to the negative side of the coil,

[demo2]

Yup i'll second that

[phil's landy]

Hi there !
I have checked on a range rover today and this wire is an earth to the o/s/f inner wing. it is black with white bands not a white tracer which as you say is from the coil ,
So i'm still strugling, any more ideas ?

[Coops]

you have the ignition relay of the ecu going to a live when in the run position have you? and not only live when cranking?

[phil's landy]

Hi there ,
Yep the relay has a live all the time with ignition on ,
The relay that buzzes stops buzzing whilst the engine runs and the starts to buzz again a few seconds after engine cuts out .
Any ideas ?

[Coops]

what wires has the relay got going to it that buzzes m8?
colour wise,
can then tell if its a fuel pump relay or ignition relay

[phil's landy]

I'll check tnite and come back to you .
Cheers Phil

[phil's landy]

Hi there,
Today i have had an auto electrician have a look at her and after all his checks he has established that the ECU has lost the wil to live ,

The reason for the buzzing relay is the ecu is only putting 6 volts to the relay for the fuel pump therefore caulsing partial operation.

So now i want an ecu for a 3.5 efi hotwire !

Thanks for you're help !

[SteveRK]

Hmm - a logical diagnosis for an engine that stops running but i would suspect either a missing coil - feed connection (black with white trace) with 6.8KOhm resistor fitted in series or some other sensor input to the ECU.

On hot-wire engines the fuel pump runs for a few seconds at ignition on and then stops. It only re-starts when the engine is cranking to start.

[bodger]

http://www.g33.co.uk/fuel_injection.htm

have a read here , " inital start up " section