Conversion Troubles ( Starts then stops)

[Lewis.J.P_1987]

Ive just done a Carb to EFI conversion on my mates comp racer using a 3.5 range rover as a doner.
It all starts and runs for about 5 seconds then it dies. Any Ideas Cheers.

[landy_bug]

check your fuel supply to carbs it might not be fuelling enough to keep it running?? other than that i don't have a clue :-k

[Range Rover Blues]

Is it a flapper system?

Check the ECU gets an ignition signal, if not it will cut out to stop fuel leaks from a stalled engine in a crash.

[Bowie]

Is it a flapper system?

Check the ECU gets an ignition signal, if not it will cut out to stop fuel leaks from a stalled engine in a crash.

Sounds classicly like this, black/white wire to coil -ve, comes from the AFM part of the loom :)

[Lewis.J.P_1987]

Thanks for the reply. Yes its a flapper system from a '87 Range Rover. Were does the ECU Get its ignition signal from? I have the Ignition cable connected. (White Wire) to a constant 12v When the kill switch is on. The (Red White) wire i have connected to the crank button. The (Purple White) wire is connected to a relay which activates the fuel pump. This is what i have understood to be the norm?

The wire I have connected to the -ve side of the coil which was attached to the airflow side of the loom is (White Green). There is no (White Black) wire on that part of this loom.

We have put a temp. fuel source to the plenum and it runs fine, but this bypasses the need for the injectors. We are waiting on a new fuel pressure regulator and a RR Fuel pump to try, as the ones we are using are off a TVR and might not be compatable.

Any more thoughts would be appreciated, Cheers.
Regards Lewis.

[Bowie]

Try disconnecting the cold start injector, see if it starts at all, if not then your injectors aren't firing at all, if it does start then die then I would say you have a fuel supply to the injectors issue, or the ECU is for some reason still disabling the injectors.

Could be a dead AFM as well, you could try manually holding the flap open to see if it keeps running, just mind you don't lose your hand down the intake ;)

[Range Rover Blues]

TVR fuel pump should be ok.

IIRC the flapper EFi uses a bank of resistors because the injectors are only 6 volt, check these resistors.  Originally they are mounted on the flapper bracket.

I still suspect it's the ECU cutting out due to a lack of sensor input from somewhere.

The Haynes manual is surprisingly good for EFi systems ;)

[Lewis.J.P_1987]

Thanks again for the response.

I Know its not the AFM as we tried two diffrent ones. And the complete setup was working before removal.
I will replace the pressure regulator on sat see if that is at fault.
Just a thought i have not connected the EAS Valve or any Oil pressure switch would this make a diffrence?

[Rossko]

http://www.gomog.com/allmorgan/ljet/FlapperSystemcheck.htm