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3.9 hotwire wiring

Posted: Sat Mar 24, 2007 8:52 am
by vdub boy 1
Hi all , new to this forum, I'm in the process of fitting a 3.9 rv8 hotwire into my dax rush kit car and was hoping if anybody can help with identifying some wires in the engine loom. I've got some answers from looking at previous posts , but being new to the world of efi (I was a running a 3.5 on strombergs) any help would be great.

On the main connector of the engine loom I have 3 wires I'm not sure what to do with , a yellow (speed transducer I think), orange/black (neutral switch) and a purple/yellow ( heated front screen according to mr haynes) can I disregard these as my car does'nt have them or do they have to be wired in somewhere. Its a 1990 discovery model (I was told) but the loom doesnt have any wires or signs of where wires have been for Lamba sensors I presume it needs them and can I retro fit them if need be.
I also have 2 black wires one thinner than the other the thinner one has a grey tracer on it both going to a ring connector, I take it these go to earth . Finally from the same convaluted tube them are two wires a grey/yellow and a white/purple which according to my wiring diagram go to a purge control valve where would this be fitted , presume I need it. Sorry for all the questions, but this seems the place to ask , thanks in advance

cheers

leigh

Posted: Sat Mar 24, 2007 9:30 am
by Coops
hi and welcome,
did you see this post with the wiring diagram????#

http://www.v-8.org.uk/forum/viewtopic.php?t=149

Posted: Sat Mar 24, 2007 10:47 am
by Ian Anderson
Purge control Valve -I haven't got it connected to anything on the Dax ad it runs

Lambdas
If you are on a 1990 engine chances are there were no lambdas present but they can be retro fitted - also then need t change the tune resistor to tell the ECU to expect lambda readings

From memory the neutral switch is for the Auto version as when not in Neutral there is drag on the engine and the ECU needs to compensate - I seem to remember somthing like a 510 ohm resistor was needed to "fool" the system (Mine is now in a manual car)

Black wires not too sure unless one comes out of the loom that connects to the air flow meter (memory says it was dark and perhaps had a light stripe on it) and that goes to the coil (don't ask me which side as I'm doing this from memory from a year ago)

Cheers
Ian

Posted: Sat Mar 24, 2007 3:35 pm
by jwriyadh
Yellow is speed transducer, you don't need it, isolate and tuck away.

Orange/black is neutral switch, for manual connect to earth via 480 ohm resistor.

Purple/yellow is heated front screen, isolate and tuck away.

Lambda sensors optional, if not fitted make sure the tune resistor(blue plug near the relays) is green(470 ohms), should definitely not be white(3900 oms). If you fit lambdas reverse above tune resistor info, terminals for ECU plug should be available from VWP.

Both the black wires need grounding on the rear of LHS cylinder head.

Grey/yellow and white/purple are purge valve, not required, isolate and tuck away.

jw

Posted: Sat Mar 24, 2007 10:11 pm
by vdub boy 1
Cheers for replies :D - really helpful. Hopeful it would be long before I can fire it up

Thanks

leigh

Posted: Tue Apr 17, 2007 7:53 pm
by vdub boy 1
Just a couple of more questions that I should have asked before , where does the efi warning pickup point wire go to, and where can i pick a suitable resistor to wire to the neutral switch to earth.

thanks

Leigh