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[Omega Steve]

Hi Guys,

Well ive tried everything thats been suggested so far and still no luck, Mark i have checked the cable for the injectors all the way accross to the ECU connector and i can see anything wrong with it, i have also tried a secondary earth from the Battery Negative to the fuel rail earthing point and still no joy, the same codes remain.

It starts up but its compensating and a little lumpy, EML is on im sure its only running on 3 as the fuel is just flowing through one of the pots, Its burning fuel like a space rocket and bellowing a blue tint smoke, fuel is still spitting out of the exhaust manifold joint I have used 2 jerry cans in the last 4 hours just testing the engine here and there.

Not sure where to go from here, im starting to thine ECU might be up the duff ? ?

Any suggestions guys ?

Steve  

[Omega Steve]

Oh i forgot to mention, i checked the ohms resistance and all the injectors register at 14.5

[Kevin Wood]

I wonder if you've got an injector stuck open?

Kevin

[Marks DTM Calib]

I wonder if you've got an injector stuck open?

Kevin

Its possible, easy to spot with an oscilloscope.

[Omega Steve]

Hi Guys,

Unfortunately i don't have an oscilloscope but i do have a collection of Injectors i got from the breakers, i have two types, all are exactly the same, one set has purple electrical connectors and the others like mine have red (out of interest do you know the difference if any ? ) i could try replacing them tomorrow, it would make sense as when the car has not been started for a while it is a pig to start, even after the cylinder head job i did, im going to test the compression tomorrow as well out of interest and see if 2 and 3 are still low. (they shouldn't be) lol i have been wondering if this fuel issue i have in some way contributed to the head gasket damage i described earlier.

Thanks again guys

Steve

[Kevin Wood]

See if you can read a part number from the injectors and compare them. The colours of the bodies are sometimes different on identical injectors and vice versa, IME, although they are often referred to by colour. However, if they are similar style and resistance and came from an engine of similar capacity the engine will at least run so they may be useful for diagnosis even if they aren't the correct injectors.

Another test would be to press the valve on the fuel rail pressure test point after it's been sitting for a while. If you don't get a spray of fuel it's likely that the pressure has leaked down through an injector.

It's possible that you've got a wiring fault that is permanently actuating one of the injectors, and this might tie in with the ECU fault code that's being stored. Are any of the injectors getting warm with the ignition on for a few minutes?

Kevin

[Omega Steve]

UPDATE:  

Unfortunately i believe i might have found my problem, im hoping you do not agree but lets see.

I rigged up a light bulb (used from the rear cluster lol) and tested for power in all the injector connectors on the plastic harness.

As i turned the engine over the bulb glow when testing Injector one and pulsed, the other 3 did nothing, now this could have something to do with the ECU knowing the engine has not fired i dont know.

I ran a continuity test from all the plug connectors to the ECU plug to make sure the wiring was alright and that tested ok on all four.

I am now thinking that its starting to look like the ECU is not doing its job ? Does anyone agree or am i overlooking something here.

Cheers
Steve

[Omega Steve]

For what its worth, i have had a good look at both sides of the ECU circuit board under a big magnify glass, tested the pins continuity to there first neighbouring circuits and all looks ok, no signs of damage, burning etc.

Also, looking at a Simtec wiring diagram i noticed the power for the injectors also travels through the Fuel Pump Relay first, another lead perhaps ?

Steve

[Kevin Wood]

When you say in the first injector the bulb glows do you mean constantly while cranking? Injector pulses when cranking will be very low duty cycle, and all injectors should be the same for a start. Too short to see with a bulb. If one is glowing it points to a wiring problem or possibly a bad injector driver in the ECU.

Kevin

[Omega Steve]

Hi Kevin,

Yes when i wire the bulb to injector 1 it blinks quickly whilst cranking, the other 3 do nothing ?

What's a Injection Driver in the ECU, is this a piece of software and is this something that can stop working all of a sudden.

Do you think i should send the ECU to a repair shop for diagnosis ?

Cheers

Steve

[Omega Steve]

Any suggestions anyone, i really want to get back on the road this week.

[Kevin Wood]

Yes when i wire the bulb to injector 1 it blinks quickly whilst cranking, the other 3 do nothing ?

I find this odd. I would expect all of the injectors to have the same behaviour but it's difficult to determine from the description if what you're seeing from No. 1 injector is correct. My gut feeling is that because injector no.1 appears to have a different signal from the others, and that there was a trouble code relating to this circuit, that something is wrong.

But.. What do you actually see on injector 1? I would expect a very quick flicker of the light every 2 rotations of the engine as the injector fires. TBH, I'd expect it to be too quick to pick up with a bulb, and only just visible if you conenct an LED to the signal.

What's a Injection Driver in the ECU, is this a piece of software and is this something that can stop working all of a sudden.

I was thinking about the hardware in the ECU which drives current through the injectors. It could be that this has been damaged although ECU failures are very rare.

Do you think i should send the ECU to a repair shop for diagnosis ?

It would be worth checking the wiring over very carefully first, in particular the run from the ECU to the 1st injector.

Does the engine run (on 3) if you disconnect injector no. 1?

Kevin

[Omega Steve]

Cheers Kevin,

When i turn the key to ignition the bulb glows and then when i crank it it flickers quickly.

I will check it out what you suggest and report back, remember i have tested continuity of all the injector wires and all seems to be ok.

Did you have any thoughts on the Fuel Relay and if that could play any part to my problem ?

Thanks for al your help

Steve

[Marks DTM Calib]

Cheers Kevin,

When i turn the key to ignition the bulb glows and then when i crank it it flickers quickly.

I will check it out what you suggest and report back, remember i have tested continuity of all the injector wires and all seems to be ok.

Did you have any thoughts on the Fuel Relay and if that could play any part to my problem ?

Thanks for al your help

Steve

When you carry out this bulb test, are the injectors still connected?

[Omega Steve]

Hi Mark,

None of the actual injectors were connected, i pulled the plastic adaptor (which fits all four injectors) off and tested individually ?

Would that cause me a problem, i still thought the ECU would talk to all for of the connectors ?

Cheers