Injector issue, maybe, I think.

[Ned Fisch]

Hey guys, so I have a little mystery going on with my TD42 GQ silver top. It has 290000 on the clock. I have had a good look through the forum and have found a few pointers to answer a few questions, but I still think I need some more tips and advice, as I'm struggling to pin point my problem and it's not the easiest thing to search right to the point. Really hoping somebody will take the time to help me out, it will be greatly appreciated.

When I got the truck, I knew there was an issue, either with an injector or two, or the fuel pump. I changed out the fuel filter, oil filters, air filter and put in new oil and drained the old fuel and filled it will 20litres of new stuff. The truck was blowing white/grey smoke on idle, once it was warm, it would blow out black under acceleration. When idling it still blew white/grey.

We did some diagnostics and found that injector number one was faulty. I bought 6 new reconditioned injectors. Also, the start/stop solenoid in the fuel pump had an edge missing from the carbon material point. We have assumed that the chipped piece had been sent through the pump, through the lines and caused the faulty injector.
Now, we have fresh injectors, new start/stop solenoid. We have tried our best to flush the pump out, and the fuel lines.

With these new injectors, I still have a mystery problem. At 1st, it was cylinder/injector number one that was faulty, now number 4 is playing up, with the new injectors. When we first installed the injectors, and had flushed the pump, we ran it, took the rig for a short drive and found that it was still only running on 5cylinders.
We cracked the nuts on the lines, to see which ones were working and which weren't. So, that found the issue of number 4. We had a good look, and thought we could see a foreign matter inside the injector. We took that one back out. I took it back to be tested. It was tested in front of me and had a correct, 100% spray pattern. The injector was kept with it's caps on and in a rag to insure there were no possibilities of anything else getting in there. The injector is back in, all the lines are back on, the firing line (1-4-2-6-3-5) are correct, and we're still having the issue with number 4.

I am dreading the worst, a valve problem, but when we first, initially checked the injectors, number 4 had no problems whatsoever. My next thought is, could it be the pump? But the pump must be okay, as we ran the car without the lines attached to the injectors, and they were pumping fuel through with no issues.

One thing we haven't tried again, is changing an injector from 1, 2, 3, 5, or 6 to 4.

Could it be a compression issue? Could it be the valve? Is it the pump? We're running out of ideas and ways to diagnose the issue.

Thank you very much for taking your time to read. Sorry for such a long description, but I think this is as short as I can make it.

[93patrol]

i would do a compression test just as a line of diagnosis shouldnt cost all that much

[Ned Fisch]

Thanks mate. I will give it a go. Still struggling on it.

[Ned Fisch]

So, I am still having issues with the beast.

Is it possible for the Injector Pump to be down on just one cylinder?

[threedogs]

the white/grey smoke is that a sign of water in the system??

[Ned Fisch]

the white/grey smoke is that a sign of water in the system??

We don't believe so, we have bled the lines very well and have put in a new fuel filter. Could that cause the issue though?

[Ned Fisch]

It can't be water, it's definitely fuel that isn't atomising. When we disconnect the 4th injector line, the grey/white smoke is removed. It seems that there isn't enough pressure for the fuel to atomise in the 4th injector/cylinder.

We have done a leak down test, and the 3rd cylinder is worse on pressure than the 4th, but the 4th is the one not atomising.

[Shaunous]

If you haven't already, swap the 4th injector with another one in your engine you know works perfect, that will at least narrow down a few things, but change nothing else, only swap 2 injectors around, say from 3-4..

Cylinder problem
Injector problem
Blocked line
Pump problem

Do this and check results.

Shaun.

[Rickie3]

seals in the injector pump could be an issue, before going to that test, the only thing is to get a compression test done, not firing on 4 could be cracked piston, crook valve,head gasket or cracked head, but get that compression test done first

[Shaunous]

Be simpler and cheaper to swap 2 injectors first and decide wether the problem moves with the 4th injector or stays with the 4th cylinder, if it stays with the cylinder then do a compression test.