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[Abiton]

I imagine you've already done this, but as well as a continuity check, you actually need to physically check all the injector wires for abrasion.  I had a problem last year caused by friction between injector wires and the main bulk of loom wires in that tray.  Wire to wire shorts between injector wires and one of the passing coolant temperature sensor wires.  Killed the CTS, but not any injectors, luckily.

[Kevin Wood]

If the bulb is glowing before the engine turns then there is a problem. You should only see very brief flickers from the light, and only when cranking the engine.

Power for the injectors is normally fed from the main relay IIRC (next to the fuel pump relay) which is actuated by the ECU. I guess they could be fed from the fuel pump relay on this setup, though. I've never looked closely.

Either way, you should have +12 volts on one pin of the injector (may need to be cranking for the ECU to switch the relay on) and the driver in the ECU grounds the other pin of the injector when it fires. Unless there's something dragging down the ground signal from the ECU to the injector I'd say it is starting to look like a problem with the ECU.  

Kevin

[Kevin Wood]

Just to add, one thing you could do is to remove the ECU, bridge the contacts on the main relay so the engine loom has power and see if the bulb on injector 1 still glows. This will tell you if the glow is a wiring problem or something internal to the ECU.

Kevin

[Omega Steve]

Interesting...... I will check it all out.....

Cheers Guys...... will let you know how it goes....

[Marks DTM Calib]

You say you buzzed the wires out for the injectors but, did you also do resistance checks to 0V and live feed?

[Omega Steve]

Sorry Mark, I don't think so, what do you mean exactly ?

Negative of each plug to earth of car ?

Im treading water a little here with the electronics but im confident i will get to the bottom of it, lol, i hope.

[Marks DTM Calib]

Sorry Mark, I don't think so, what do you mean exactly ?

Negative of each plug to earth of car ?

Im treading water a little here with the electronics but im confident i will get to the bottom of it, lol, i hope.

Measuring the resistance between each injector wire and 0V (no such thing as an earth on a car).

The way I see it is that we need to be sure that there is no low ohm connection between the injector wiring and 0V (the ECU is a low side driver on the injector feed) before pointing the finger at the ECU.

[Omega Steve]

Ok, this might sound crazy but how do i do that ?

I have measured the resistance of the actual injectors and they were 14.5 Ohms

Where do i get a 0V from ? and i will go check them all now, (you do mean all 8 connectors off the loom that plugs onto the injectors right) ?

I always thought the chassis of the car was all 0V earth ?

Thx

[TheBoy]

Ok, this might sound crazy but how do i do that ?

I have measured the resistance of the actual injectors and they were 14.5 Ohms

Where do i get a 0V from ? and i will go check them all now, (you do mean all 8 connectors off the loom that plugs onto the injectors right) ?

I always thought the chassis of the car was all 0V earth ?

Thx

The engine/chassis is all 0v.  There is no earth on a car (unless you have the earth straps that rub on road).  Its technically incorrect to call the chassis earth, but many people do.

[Marks DTM Calib]

Ok, this might sound crazy but how do i do that ?

I have measured the resistance of the actual injectors and they were 14.5 Ohms

Where do i get a 0V from ? and i will go check them all now, (you do mean all 8 connectors off the loom that plugs onto the injectors right) ?

I always thought the chassis of the car was all 0V earth ?

Thx

Correct, the chassis is all 0V but, is not earth. Unless you have driven a bloody great spike into the ground and connected the car body work to it!

[Omega Steve]

[/quote]
The engine/chassis is all 0v.  There is no earth on a car (unless you have the earth straps that rub on road).  Its technically incorrect to call the chassis earth, but many people do.[/quote]

ah, I see what you mean.....

[TheBoy]

Ok, this might sound crazy but how do i do that ?

I have measured the resistance of the actual injectors and they were 14.5 Ohms

Where do i get a 0V from ? and i will go check them all now, (you do mean all 8 connectors off the loom that plugs onto the injectors right) ?

I always thought the chassis of the car was all 0V earth ?

Thx

Correct, the chassis is all 0V but, is not earth. Unless you have driven a bloody great spike into the ground and connected the car body work to it!

I've seen an Escort van skewered on one of those concrete bollards - does that count

[Omega Steve]

Correct, the chassis is all 0V but, is not earth. Unless you have driven a bloody great spike into the ground and connected the car body work to it![/quote]


LMAO : Ok i get it, (but maybe that will help my injector to work) lol only j/k

I will let you know what results i get from the Ohms test, thx Mark.

[Omega Steve]

Ok, that was very Interesting, i think.

Measured the Ohms on all 4 and number 1 is what i think the term is called grounded.

results were

Injector 1 +  00.6
Injector 1 -   01.2

Injector 2 +  0
Injector 2 -   01.2

Injector 3 +  0
Injector 3 -   01.2

Injector 4 +  0
Injector 4 -   01.2

So i guess Injector 1 should not be giving a reading on the + side, also i get a closed circuit between that and 0V unlike the other 3 injectors which are open circuit.

Hmmmmmm

[Kevin Wood]

So, injector 1 is 0.6 ohms and injectors 2-4 are open circuit (not zero ohms as you have written)?

Does that reading change when you unplug the ECU?


Kevin