Help solve my MK2/MK3 wiring please!

[euro dave]

Hi,

Some of you know I have a MK2/MK3 hybrid.  Well, on the way home from Mallory Park the other day the car gave up and cut its fuel supply.  The RAC guy took one look at the wiring, had a go, then gave up.  We ended up on the back of a lorry.

So I've spent a while over the last ten days ripping out what's not needed, including the TOAD immobiliser, and ended up with only a handful of problems.  Please bear with this post - it's a lot of info.

Small pics can be found at

http://www.teamshock.co.uk/forum/album_cat.php?cat_id=325&user_id=4

The background:  It's a MK2 1.6 Ryder loom, with the engine loom and ECU being a MK3 2.0 8v.  The entire drivetrain and fuelling is MK3.  The previous owner left the MK2 loom where it was, and fed the MK3 ECU/engine loom in through the bulkhead on the passenger side because they couldn't be fussed routing it properly, or perhaps the loom had just been cut clean and there were no connectors.  Either way, that leaves a few issues of how to connect up all the MK3 engine stuff to the MK2 loom.  I think what has happened in effect is what someone would do to wire a MK3 loom into an early MK2 loom.

So, there are some spliced wires running from the fuse box over to the MK3 loom.  Things such as G2/3, G2/4, G2/10, G2/11, F/7, A2/1 and L/7 using the (useful) fusebox FAQ.

I'm not bothered about these.  They're a bit of a mess but it's obvious what's going on - it's just feeding the MK3 loom/ECU.

The issue starts with the fuel pump relay.  In a moment of insanity the previous owner has wired in their own relay (this broke on the way home from Mallory).  The low current inputs are G1/4 and a blue/yellow wire from the MK3 loom.  The high current output feeds the fuel pump, a lilac/white wire (MK3 loom) and a red wire (MK3 loom).  The power input is from H1/2.  My plan is to get a MK2 connector and MK2 relay and redo this so the power comes from the fusebox as it should (will MK3 stuff do?).  The problem is why does the output also supply the red and liac/white wire?  Can I just feed these wires straight from H1/2?

There are also a couple of other wires coming from the fusebox into the MK3 loom which I'd like to know what they do.

G1/4 feeds a Black and also a Black/Yellow wire in the MK3 loom.
F/1 feeds a red (and then red/black) and also a small red/green wire in the MK3 loom.

If you also look at the pics in the link, you can see I have an absolute bare minimum of relays, and I thought I should have an ECU relay somewhere?  Comments would be very welcome!

Thanks

Dave

[dan7]

  x 1,794,754!!!!

[rubjonny]

do you want a complete MK3 wiring diagram? I think this would help you out considerably! pm me your email addy and I'll send you it.

fuel pump loom depends what pump you are using, IIRC it was a MK3 one right?  if so any mk3 fuel pump loom from the scrappy will work, all the plugs on the pump are the same. its completly seperate too, runs to its own plug on the rear of fusebox. Just need to hack open a MK3 rear loom to remove it
also pinch a relay from same car, 80, 67 or 167 is what you need, bottom right.  You also need 30-30b jumper wire from the back of the fusebox if not present, then its just an earth trigger wire from the ecu to G1/3.

G1/4 is ignition (coil) live, this will power up the coil, vac canister, speedo sensor etc, stuff like that.
F/1 is starter motor trigger, red/black is the starter the green will be for the ecu or sometimes an alarm module