raywin
Well-Known Member
One last thought I measured the resistance of the injector pins at the plug
A1, A24, A25, A26, A27, are the injector pins the commons are A22, A23
Each pin had a path to one or the other commons with a resistance between 1.6 and 1.9 Ohms
Each pin had a path to one other pin with a resistance of about 2.8 Ohms.
Did not understand why each pin has a connection to one other pin, has anyone else checked this ?
Would be interested to hear the readings from a known healthy system.
A1, A24, A25, A26, A27, are the injector pins the commons are A22, A23
Each pin had a path to one or the other commons with a resistance between 1.6 and 1.9 Ohms
Each pin had a path to one other pin with a resistance of about 2.8 Ohms.
Did not understand why each pin has a connection to one other pin, has anyone else checked this ?
Would be interested to hear the readings from a known healthy system.
Tim4x4
Well-Known Member
I will check the reading on my one, but it will not be until Sunday.
raywin
Well-Known Member
Thank I appreciate that, can't figure the connection between the positive pins
I bought a new injector harness and I will fit it on Sunday just to cover all the possibilities.
Tim4x4
Well-Known Member
I do not know why the connections are common on three and two injectors, the only thing that comes to mind is limp home mode. The ECT having the ability to cut either two or three cylinders as a protection from damage but retaining some power to get out of trouble. Hopefully an expert will have an answer for us.
Looking at the wiring diagram another thing that seems odd is the wire from pin 22 it changes colour from NK (brown pink) to NB (brown black) at a connector.
raywin
Well-Known Member
I wondered about something like that but of course I am measuring with the plug disconnect from the ECU so just measuring the lead and the injector solenoids in the head.
Tim4x4
Well-Known Member
I have just taken the readings from my RED plug and it is very consistent-,
Between pin 22 and 24 = 1.5 Ohms
22 and 25 = 1.5
22 and 27 = 1.6
Between pin 23 and 1 = 1.5
23 and 26 = 1.5
Any help?
raywin
Well-Known Member
Thanks that looks like what I see, so probably good, did you make any checks between the pins: A1, A24, A25, A26, A27, i.e. between the live pins rather than live to common, that's the bit I found confusing that some are wide open and some have a resistance of <>3 Ohms.
Put in a new injector harness today and its no go, so I have decided to opt for a repair rather than a second hand unit, its a bit more expensive but a second hand one may only be 6 months away from the one I already have and leave me high and dry.
Tim4x4
Well-Known Member
No I did not make those tests I do not understand what that would be testing?
Tim4x4
Well-Known Member
No did not take the readings from the injector feeds, not sure what that would be testing but as you I am confused by the reading you have. I would have thought it would be open when the red plug is removed. I will do them for you as a comparison to your readings but am stuffed for time now until Tuesday.
raywin
Well-Known Member
I understand the tests you made, in these we were testing the lead to the injector coil and the resistance of the attached coil, they look just like mine so I am happy the coil resistance I see is very similar to the resistance you see. ,
But as an extra test I jut tested between each + pin and all of the other + pins,l and what confused me was that in each case there case a connection between the + pin on test and just one other + pin. But the rest were open circuit.
So each + pin was connected to a a partner,
But as an extra test I jut tested between each + pin and all of the other + pins,l and what confused me was that in each case there case a connection between the + pin on test and just one other + pin. But the rest were open circuit.
So each + pin was connected to a a partner,
Tim4x4
Well-Known Member
managed to do the tests
24 and 27 = 2.8 Ohms
24 and 25 = 2.7
25 and 27 = 2.8
1 and 26 = 2.7
raywin
Well-Known Member
Thanks for your help here, this has set my mind at rest now, sorry to put you out in the cold on a Sunday afternoon.
Even if I don't fully understand it there is a connection between some of the live pins, makes me feel more relaxed that your working harness measured up the same as mine, so I feel the injectors will be good and the crank sensor is OK.
So decided to go with the ECU repair, with warranty and I have packed mine up now ready to ship it. Works out just over £300 but that's life.
raywin
Well-Known Member
Well just called them and they say no fault found just what i did not want to hear, tried to get me to have it re built anyway saying it might have an intermittent fault.
So back at square one, I may take out the starter and check the contacts I understand they can cause problems, better look at the fuel pressure regulator too.
So back at square one, I may take out the starter and check the contacts I understand they can cause problems, better look at the fuel pressure regulator too.
neilly
Well-Known Member
Well, that sucks......
regarding the starter motor, only one I have come across where the contacts had gone it would click as the rod moved but do nothing more as the contacts were not touching to transfer the electrickery, But it may be advisable while you are in there to replace anyway. Cheap and may stop it happening in the future.
Have you checked the fuel pressure? with a guage?
Might be worth restating what the problem you are having.
Cheers
raywin
Well-Known Member
Well back to basics, the engine started to cough and shake while ticking over on the drive, then it cut out and it wont start, sometimes it coughs and spits out grey brown smoke as if it is firing but all wrong.
Changed crank sensor and wires, changed injector harness and I have checked the connections from the red plug on the ECU all seems to read OK. Nanacom shows peak charge high and peak charge low for all 5 injectors.
Thinking this through starter must be low down on the list, as the problem kicked in when the engine was already running.
I tried the fuel pump early in the game by pulling off the return pipe from the fuel cooler, putting it in a fuel can and turning on the ignition, it half filled the can in a short time and seems to have a healthy delivery rate.
Just ordered a fuel pressure regulator in case it has given up and just allows the fuel to return without holding any pressure in the head.
Changed crank sensor and wires, changed injector harness and I have checked the connections from the red plug on the ECU all seems to read OK. Nanacom shows peak charge high and peak charge low for all 5 injectors.
Thinking this through starter must be low down on the list, as the problem kicked in when the engine was already running.
I tried the fuel pump early in the game by pulling off the return pipe from the fuel cooler, putting it in a fuel can and turning on the ignition, it half filled the can in a short time and seems to have a healthy delivery rate.
Just ordered a fuel pressure regulator in case it has given up and just allows the fuel to return without holding any pressure in the head.
I can't really add anything because you're looking at all the things I'd be looking at anyway.
Sounds like you've been using ecu-testing.com, which was where I sent mine back in October when I had a cut out and non starting issue. Fortunately their £300 ministrations fixed my problem. Which is cheaper than a new ECU, so probably worth it.
A fuel pressure tester is a tool well worth buying if you have a TD5. It's such a key diagnostic issue. I got one a while ago and I don't know how I managed without it.
I've found that those peak charge long/short or low/high errors come up when my injector loom is on the way out. Whilst yours is likely good, there's always the possibility of an intermittent fault elsewhere in the wiring looms as Land Rover seem to have used a duff batch of wire in the mid 2000s, with tender insulation and brittle conductors. I splashed out on a new engine loom a couple of years ago. It was in the region of £300, but things have been much better since.
Sounds like you've been using ecu-testing.com, which was where I sent mine back in October when I had a cut out and non starting issue. Fortunately their £300 ministrations fixed my problem. Which is cheaper than a new ECU, so probably worth it.
A fuel pressure tester is a tool well worth buying if you have a TD5. It's such a key diagnostic issue. I got one a while ago and I don't know how I managed without it.
I've found that those peak charge long/short or low/high errors come up when my injector loom is on the way out. Whilst yours is likely good, there's always the possibility of an intermittent fault elsewhere in the wiring looms as Land Rover seem to have used a duff batch of wire in the mid 2000s, with tender insulation and brittle conductors. I splashed out on a new engine loom a couple of years ago. It was in the region of £300, but things have been much better since.
