4age running on 3 injectors???

[Alexii]

Got my exhaust done on my car today, took it for a drive and noticed it really wasnt going anywhere...

I have found that injector 3 isnt working, there is power to the injector plug, thers spark on all four leads and i have also swapped injectors around and injector plugs but that 3rd injector is still not working! Also have noticed when i take injector 3 out of the fuel rail its has heaps of pressure behind it

Has this happened to anyone before or does anyone know the problem?

[slide86]

so even after you swap the injectors the fault is still on cyl 3?

there is supposed to be alot of pressure in the fuel rail, so that is not a fault.

[Alexii]

Thats right i swap the injectors around and the fault is still on cly 3.

There is supposed to be pressure in the fuel rail but not that much when i took out the other injectors they didnt have the same amount of pressure at no 3 did so im guessing it might be blocked?

[slide86]

yeah it might be blocked (that one injector) but it doesnt explain what your current fault is. because you have swapped other injectors into that cyl and the fault is still there, it rules out an injector.

if you have a noid light, plug it into the injector plug on the loom and see if it flashes. if not then you will manually need to check the loom for an open circuit.

the injector is earthed through the ECU, this is what turns the injector on and off. It always has a 12v signal on one side (when ign is on), so if you have that 12v signal then there must be an earthing fault.

I would say that you MAY have an internal ecu fault if your other diagnostic steps havent revealed the fault.

[Alexii]

Thats right its weird i swap injectors around and its still no 3 on the fuel rail, i have checked for power on the plug and both terminals have a solid 12volts

also i have swapped injector plug 4 with 3 and injector plug 4 which is working doesnt work on no3, the fuel rail must be blocked on no3 on the fuel rail

[Javal]

Thats right its weird i swap injectors around and its still no 3 on the fuel rail, i have checked for power on the plug and both terminals have a solid 12volts

also i have swapped injector plug 4 with 3 and injector plug 4 which is working doesnt work on no3, the fuel rail must be blocked on no3 on the fuel rail

The injectors power up when they're earthed (negatively switched), they have power all the time if memory serves.

Use a Noid light (or, if you don't have one, a test light, one end to the power side and one end to the trigger earth side) to check if it's being triggered.

If you have no trigger, check continuity in the wiring harness.

If you have a trigger, some funky shit is going on.

You said you've swapped the injectors over, no?

[Alexii]

Do you mean check if one terminal on the injector plug has hard power and the other terminals flashers?

Yes i have swapped the injectors over and its always the 3rd one that isnt working and i have swapped over the injector plugs and still isnt working so the 3rd injector plug has to be fine

[slide86]

the plug is just the plastic part that clips to the injector. it wont really make any difference by swapping these around

so by swapping the plugs you must have backed out the terminals of each plug and then refitted them when you swapped over? make sure that the terminals are contacting correctly when you push the plug back on the injector.

im not 100% sure that there should be 12v on BOTH sides of the plug, definetly one side but like i said before, the trigger wire is EARTHED through the ecu so it shouldnt have a 12v signal on it.

[Skylar]

I think it went like this:

Plug on injector: both wires will read 12v
plug off injector: one wire will read 12v

[slide86]

correct.

when the engine is running it will show 12v on both wires with the plug ON the injector.

However, this is actually not 100% true. the signal is pulsing on and off, and a multimeter cant actually read fast enough to catch the open circuit stage, which would show 0v on the trigger side.

this is where a special tool called a NOID light comes into play. its specifically designed to read and show this pulse effect with a small globe so you can confirm that both the power and trigger sides of the circuits are operating correctly

[jdm86gtz]

The Yellow wire should have 12V with ignition on, injector 2 and 4 should have a Red wire on the other pin and injector 1 and 3 should have a Blue wire on the other pin. As these are batch fired all 4 injector wires connect together somewhere in the loom.

[Alexii]

Ill test all this tomorrow but like i have said and i find it weird is that if i put the number 3 injector plug which isnt working on injector 4 it works and when i put number 4 injector plug which is working on number 3 it doesnt work do you get what im saying? I dont think that injector 3 plug isnt plusing it might be some thing else?

I will check for all the above tomorrow and do a couple of tests aswell

if anyone does have more ideas please post up i want to sort out this problem

[VTAZ!]

LMAO ill give u 5 bucks for it

[Skylar]

haha, I wasn't even thinking about engine running. Can you get DMM's which show PWM value? or just use the frequency function on DMM to determine if a frequency is present at the trigger side?

[Alexii]

LMAO ill give u 5 bucks for it

ill give you 5 for your panzy spec 86 that my grandmother should be driving
even she will fatten thhat thing up!

[Chrisso]

in place of a noid light I use a led jammed in a tube (old pen, roll of paper, piping) so you can see it flashing better. Stick the legs of the led light into the loom plug for each injector and crank.

[Javal]

in place of a noid light I use a led jammed in a tube (old pen, roll of paper, piping) so you can see it flashing better. Stick the legs of the led light into the loom plug for each injector and crank.

This is a darn good idea.

[Alexii]

Injector 3 started working when i moved the plug around but now sometimes the coil doesnt produce spark and sometimes it does.

Could this be caused by a loose wire or bad earthing point?

[Javal]

Injector 3 started working when i moved the plug around but now sometimes the coil doesnt produce spark and sometimes it does.

Could this be caused by a loose wire or bad earthing point?

Intermittent break in the injector harness.

Coil is likely to be a separate issue.

[biggo]

its caused by ether, dont fight that shit man.

[Alexii]

was checking the coil out today, the coil is gettin power on the positive side and the negative side? is the negative side supposed to have power going to it?

also this sparking issue started after it came back from the exhaust place maybe they welded the exhaust with the battery on and burnt the computer out is that possible also?

[Javal]

was checking the coil out today, the coil is gettin power on the positive side and the negative side? is the negative side supposed to have power going to it?

also this sparking issue started after it came back from the exhaust place maybe they welded the exhaust with the battery on and burnt the computer out is that possible also?

Uhhhhhhh.................

[Chrisso]

Uhhhhhhh.................

Translates to, "the negative side is connected to the ECU which grounds the coil to fire the spark plugs."

Unfortunately I'm unsure of how to tell whether your ecu is stuffed.

[VTAZ!]

project FAIL BAP! LOL

[Alexii]

all up and running guys cheers!

[slide86]

what was wrong with it??