Thread: 14CUX- which wire is power feed?

Plug 13 ( end of bottom row), yellow /blue on my 89 wiring diagram is battery. The colour may change but the plug will be the same.

If you still cannot work it out I have the wiring diagram and pin outs on my Project for fittng O2 sensors.
PM me your email address and I will email it.
Regards Philip A

Thanks Philip . Unfortunately nightshift beckons so I won't get to it for a few days, but the diagram would be a great help

There are a number of ways to cut the injectors. The way I use is to find the brown/orange trace wire/s in the main loom to the engine which feeds the injectors. Depending on where in the loom you are there could be 1, 2 or 3 wires of this colour. Cut the one or two fat ones, (join either side of the cut to one wire), and fit a relay. The thin one powers the hotwire MAF if that's what is in yours. If the MAF feed is downstream of the injector cut look for 12 volts appearing at the brown/orange trace wire at the MAF. You may have to feed the MAF from before the injector cut. It is best to leave the MAF powered while on gas.
The other common way to cut the injectors is to find the two wires that connect the two banks of injectors to the ECU (yellow/white trace and another similar, check at the injector plugs). You will need a double relay. The best relay for this purpose is the APEXUS model CO202 petrol start relay. It remains closed circuit until power is applied from the gas system, then it switches off the injectors after a short (adjustable) time. This gives a petrol assisted start as well as a backfire free changeover between fuels.

Just the sort of info I was hoping for BeeUtey, I'm just going out the door to work the next couple of nights, soon as I've slept it off I'll investigate armed with your info and Philip's diagram, thanks again.

Got this done last night with the help of this info. Installed 2 relays into the wires that exit the ECU for the two banks of injectors, used the petrol/gas start timer off my old beast, drew up a circuit to run it all and it works a treat. I now have the fuel pump running all the time whether on gas or petrol, the fuel circulating through the rail is supposed to prevent the injectors overheating and seals drying out. This car had been gas-only for 5 years, when I installed a petrol tank and wired up the pump, I got a big puddle of petrol under the engine- all the injector seals had hardened and shrunk, so it certainly is an issue. The injectors were completely gunked up too.
I might install a switch to override the pump in case the little tank runs low. Thanks again for the help.

Originally Posted by bee utey

You may have to feed the MAF from before the injector cut. It is best to leave the MAF powered while on gas.

When I switch my MY95 Disco from LPG to petrol on the move it runs rough. I have to switch the engine off and let the ECU reset and then restart the engine on petrol to have it run properly.
My code reader always shows a MAF fault if I've run it on LPG since resetting the codes.

Would it be safe to assume the installer has cut the power wire before the MAF and I should find where it has been cut and power my MAF from before the cut?

Although my system does have a petrol start (variable time length) relay. I better test for power on the MAF wire sometime as having to restart it after switching is really annoying.

......as a add on here 14CUX wiring loom colours used in Classics and D1's in the D1 changeover period around 94 were a dogs breakfast so I suggest always trace back to ECU pin outs to be sure as LR wiring diag/ RAVE / Haynes etc wiring colours can't be trusted for looms of this vintage.

Originally Posted by Utemad

Would it be safe to assume the installer has cut the power wire before the MAF and I should find where it has been cut and power my MAF from before the cut?

Exactly what I found the first time I converted a D1. Worked it out before I handed the car over and now I check all cars for sensors wired to the injector circuit. In your case just probe the brown/orange trace wire at the MAF while on gas. If no 12volts just cut the feed wire and run a new feed from the ECU side of the injector cut.
BTW the brown/orange trace wire for injector feed is standard across all V8's with EFI from '85 to '02 at least. Never met any other.