Board logo

Injector wire size... injectors not firing
furryeggs - 28/7/17 at 07:30 AM

So I'm having an issue getting my blacktop running. Before i rewired new injector plugs it ran ok and fired first time. Now however it won't start. Nothing else has changed other than the injector loom/plugs. Stupidly I haven't got the original plugs so i can't swap them back over to check. With the new plugs i used new wire as well wich is a different gauge. Is this going to of dropped the impedance enough to not fire the injectors.

I've checked That I've got 12v at the injector all the way to the plug, the ecu is seeing the the crank sensor, i have 12v at the coil and test lights on the spark plugs so I can see them firing. I have fuel at the rail as well but no smell of petrol in the TBs.

2.0 blacktop
Hyabusa TBs
Emerald K3 ecu


britishtrident - 28/7/17 at 08:10 AM

The injectors don't take a huge current only abiut 3 amps peak for a very short pulse, modern cars have very skinny wires to the injectors.
Test the control (ground) wires to an injector with a test standard light wired to battery positive if you don't see the light flickering you have a problem with the control side wiring to the ecu.


furryeggs - 28/7/17 at 08:57 AM

Well, I've just had a re test with the meter and although i had 12v at the injectors and coil I was loosing in when cranking. I had used the the 1st position key supply for the coul when re running the wires. I bypassed it with a fused supply direct to the battery and it fired straight up. Rather than running new wires can i use an unused dash swicth as a type of immobiliser switch? that way the 12v won't be perminatley on the coul etc.


britishtrident - 28/7/17 at 12:35 PM

The ignition must be getting power from the "ACC" terminals on the Ignition switch not the "IGN"

See this link to the Holdens Classic parts website

[Edited on 28/7/17 by britishtrident]


Angel Acevedo - 28/7/17 at 03:00 PM

quote:
Originally posted by furryeggs
Well, I've just had a re test with the meter and although i had 12v at the injectors and coil I was loosing in when cranking. I had used the the 1st position key supply for the coul when re running the wires. I bypassed it with a fused supply direct to the battery and it fired straight up. Rather than running new wires can i use an unused dash swicth as a type of immobiliser switch? that way the 12v won't be perminatley on the coul etc.


If you feel so inclined, Iīd put it behind the dash, or below the seat in an inconspicuous location..
a friend of mine had rigged his truck with a bare wire laying under his seat between the mat and a plastic mat on top...
You had to touch it to start the car...
Else, the engine would crank but would misfire and wouldnīt start.
I donīt know how he accomplished that...