wiring gurus help please, tricky one

[richyx]

ok this may or not make sense but ill do my best lol

i got another car loom to fit in my car but after investigation the coil plugs ignition amps have been cut out completely, knock sensor as well, a link wire from ignition live to coil wire and various other things

so im going back to my original loom as im still able to use it after i thought it was water damage but it turns out the central locking loom was knackerd lol

so with my loom i completely removed the engine loom, every wire from ecu plug which left me with a bunch of wires left over to join an uprated engine loom on

now this is my problem

so far the wires i have are

oil press light
oil pressure gauge for pod gauges
water temp gauge
rev counter

i have a black/red wire which im guessing is live as it has reds linked off it
black wire switched ignition
brown earth

then came the tricky part after testing wires i had one which went to the abs ecu, this was then found it went to a diagnostic port in engine loom so not needed, same with a red/brown for abs light but again goes to diagnostic

im now left with one wire

this goes to pin 85 of relay r8 in the fusebox, this relay is for lambda

now what do i do with it, this wire sends a signal from ecu to relay for lambda but ive removed my ecu connector as ive taken the loom out

do the after market looms come with this wire to power the relay up for the lambda? if so great if not im stuck

i know the after market looms have lambda connection, but how many wires, do they have 3 2 to ecu and one power or just 2 for ecu and i take power elsewhere, but it still leaves me with this wire from ecu to lambda relay

any suggestions on what to do?

[DAI COSSY]

I did this ,sort of your making it complicated,all you need is a stand alone loom like James would make powered direct from batt then a trigger wire to live it on ignition,then all you need out of that bunch is oil press,Rev counter,water temp, the rest runs within ecu,I've used msd fuel pump looms so I'm not drawing any power through fuse box to run my car the car runs stand alone I'm even using fan looms as well so I can minimise fuse box issues this is how I've done it admitted its not for purists but it effectively won't let you down easy to work on and spot or test problems it's not like your cars not modded either it would be less grief for sure

[L953LNE]

Is that what i'd be best doing Dai, not at that stage yet but will be getting a new engine loom. and MSD fuel pump loom, Think the full car loom is there but haven't got stuck into that yet.

[richyx]

yes the ecu controls lambda but does it have its own relay in the new loom? if not then it need it sends power down to the original relay

[DAI COSSY]

Is that what i'd be best doing Dai, not at that stage yet but will be getting a new engine loom. and MSD fuel pump loom, Think the full car loom is there but haven't got stuck into that yet.

Yes the full loom was there but as I had done the above,for 2 reasons
1- I don't trust mk5 escort or any cossy fuse boxes
2-reliability/no power drain etc

yes the ecu controls lambda but does it have its own relay in the new loom? if not then it need it sends power down to the original relay

Sorry rich your loosing me don't know what you mean,it's
all ecu controlled to my knowledge on mine
Power comes from battery to direct to loom
Ecu loom powers up by a trigger live nothing more to it really

[matt cooke]

The ecu sends an earth to the injection relay to power up the heater circuit on the oxygen sensor. I think you just need to see what comes with the new loom mate

[James @ Auto Dynamix]

Lambda is normally powered from the fuel pump relay, purely so the lambda heater is only active when the engine is running so the exhaust gasses cool the heater to prevent failure.

[richyx]

this is the problem, after we got round what was the abs wires, i was left with two wires from ecu

one goes to r9 pin 85 whch is fuel pump, the other is this one from ecu to pin 85 on r8 which is lambda

so the ecu either recieves or sends a signal down to this relay to turn the heater on the lambda

if the after market looms dont come with this wire how can the lambda heat up but even more so what does the relay do with this wire not going anywhere

[matt cooke]

Lambda is normally powered from the fuel pump relay, purely so the lambda heater is only active when the engine is running so the exhaust gasses cool the heater to prevent failure.

Not sure about that mate

[matt cooke]

What are the benefits of these aftermarket looms? Is it to bypass the shit ford fuse box?

[James @ Auto Dynamix]

Bypasses the fuse box, and all the old shit ford engine loom which has had 1000s of heat cycles.

Most if not all aftermarket looms will power Lambda from fuel pump. its the right way to do it. If you leave a lambda powered with no exhaust gases passing over it, it will fail.

Theres info on my looms on my website.

www.performanceislooming.co.uk

[matt cooke]

Sounds like the right way to go mate

[matt cooke]

I deffo need to change fuel pump loom on mine

[James @ Auto Dynamix]

I make fuel pump looms for the Escort,

[richyx]

you have 4 wires for lambda in a std engine loom

3 go from ecu to lambda plug, on goes from ecu to this lambda relay not fuel pump

i lambda does need a relay for the heat element, so ideally i need a loom that has this wire from the ecu to the std lambda relay