Defender td5 90 farmers spec

Hi
I have just rebuilt my defender new chassis bulkhead etc
But it fires for a milly second and then just cranks over.
I have tested all the relays and the pump has 5 to 7 bar when cranking.
Do you know If a td5 90 with out a key fob or Alam has an imoboliser it has a green box in the dash.
It does start sometimes and then just stops and won't start again.
Thanks

Yungy

Yes they do have an imobilizer. Mine won't crank if imobilized. Non starting could be crank position sensor

Hi
I had it plugged in to diagnostics tonight and it is showing the following faults.
Injector peak charge long on all 5 injectors.
Before a kind man came to plug it in I reinstalled the ecu as I took it off the night before and it sat in the kitchen at this point the fairy must have come because it started and ran fine for a bout 10 minutes and then cut out.
Any ideas
Regards

Yungy

Possibly injector loom, or more likely
Faulty ecu.

Mine shows a 'peak charge long' error code when the injector loom is getting oil in it. So it might be something simple. Fingers crossed, eh?

Thanks for the replies.
It seems when the ecu is not connected to the batt it's doing something like de-energising and then it will start for a bit.
The positive batt terminal is getting hot so I going to recheck the earths.

Thanks

Also, if the positive terminal is getting hot, it's worth taking the clamp off and cleaning up the contact surfaces. Maybe you're getting a voltage drop. TD5 ECUs are sensitive to voltage and if it's low, they won't work.

Brown said:

Also, if the positive terminal is getting hot, it's worth taking the clamp off and cleaning up the contact surfaces. Maybe you're getting a voltage drop. TD5 ECUs are sensitive to voltage and if it's low, they won't work.

Click to expand...

That's good advise for any vehicle, thanks for the reminder.

Hi
Cleaned the batt terminals
Checked stripped and cleaned all relays.
Checked earths with ohms meter the resistance is perfect when it's not running but when the ingition is on with the engine running yes engine running the earths are showing a lot of resistance,I don't know if this is normal.
Took it for a run and tested it for about 30 mins.
Got it home and let it tick over for 20 mins and it's fine.
But I don't feel like I have found the problem for some reason.

Thank for the comments

Yungy

Yungy said:

Hi
Cleaned the batt terminals
Checked stripped and cleaned all relays.
Checked earths with ohms meter the resistance is perfect when it's not running but when the ingition is on with the engine running yes engine running the earths are showing a lot of resistance,I don't know if this is normal.
Took it for a run and tested it for about 30 mins.
Got it home and let it tick over for 20 mins and it's fine.
But I don't feel like I have found the problem for some reason.

Thank for the comments

Yungy

Click to expand...

You cant measure resistance with the engine running. There will be a slight voltage over the length of the lead when there is power going down it (i.e running), that will muck up any attempt to measure resistance. What you actually need to do is accurately measure the voltage across the earth lead i.e measure from the chassis to the battery -ve terminal (the actual battery stud bit itself and not the clamp) that way will also check how good the lead connection is from chassis to battery including attachment points. I would guess that you need to be somewhere around the 0.1 to 0.2 volts region, any more than that is worth having a look at.

Thanks for the help that's really useful
Green relay is getting hot now but it's still running.

Thanks
Yungy

Ok thanks for the help so far.

Checked all the earths and there all at 0.2 ohms so there good.
Check the continuity between the ecu and injectors ..all good.
Checked the feeds into the ecu all good.
Now I took it for an mot and the went out in it and about 1 hour into the drive it stopped and would not start I towed it back home and left it.
Tried to start it in the morning and bingo it start perfect.
Now on the diagnostics it coming up with
Injectors 1 to 5 peak charge long that will not clear.
So does anyone want a job supply and reprogram a msb101171 or something that will fit.
I think it's the ecu failing when it's warm.
I have stripped my ecu and there is no signs of oil or dry soldered joints.
Cannot understand this as the thing was working perfect before I changed the chassis.

Thanks

Yungy
Oh I am in Chester

i would check your loom and make sure you haven't nicked the cable somewhere which is causing it to short and heat up

As already said, either injection loom or faulty ecu