More 3.9 hotwire help needed

acs · Post by **acs** » Wed May 09, 2007 7:46 pm

Right quick summary of where I am.

I had a 3.5 Rover V8 Carb'ed in my Land Rover 90 that had head gasket issues.

I found in the back of someones garage a 3.9 Efi with loom but no relays ecu or MAF sensor. Motor has allegedly done 33k before being removed for a diesel.

I have taken the Mallory Electronic Ignition Distributer from my old 3.5 and fitted it to the 3.9. (Without trying the old setup which I have no coil for.)

I have connected the old 3.5 loom around the engine to all the sensors alternator and dizzy.

I have taken the efi loom and connected it as instructed in your very helpful thread above on connecting a hotwire. Found the resistor in the loom from the coil. (That was fun)

I know I now have compression and I believe the timing is good.

Now my fun. There is connectors on the loom for 3 relays. How many of these do I need. If so which ones and do you have the part numbers I need to order replacements?

Is there a jumper a can create in the relay loom so I can test the motor to see if it's worth investing yet more cash into this motor?

Is there any voltages/readings I can take on the ecu fuel sensors of injectors to try and fault find my mess of unknowns.

Is there anything I can test from the MAF I have aquired for the engine?

Basically is there anything I can test any fault finding I can do?

Thanks for reading this and for any replies

Hoping for a running V8 EFi soon
Adi

hearbear · Post by **hearbear** » Wed May 09, 2007 9:51 pm

Get a range rover haynes manual as this has a good section on checking the sensors and all output voltages and inputs. You need two relays which are N/O with twin outputs (they also have a small block diode fitted to stop back feed) and you should be able to check the wiring diagram to see which two need fitted. You should be able to get from any landie supplier I picked up 2 for about £10.

George

acs · Post by **acs** » Wed May 09, 2007 10:02 pm

Cheers for that. Manual now on it's way.

I was trying to talk to my local Land Rover dealer about the relays on Tuesday and they where clueless. I was trying to have a dig round in their microcat system to find the part numbers but they wouldn't let me

ChrisJC · Post by **ChrisJC** » Thu May 10, 2007 12:10 pm

The 3.5 flapper has a set of 3 relay sockets. Two are black, one for the main relay, the other for the fuel pump relay. The red socket is for a 'current steering module' which is in fact a bunch of diodes inside a red relay case.

Maybe your setup is the same.

Chris.

acs · Post by **acs** » Thu May 10, 2007 2:30 pm

I'll have a check. Definatly got two black sockets and I think one blue.

Thanks
Adi