td5 misfire

[quaddrive]

Any advice greatly appreciated.

I have a 2003/2004 defender 90. It developed an intermittent misfire that could often be reset by switching the car off for a bit. This degenerated into a constant misfire, this was diagnosed via testbook at rovatech as no. 5 injector not operating.

This was then removed and tested to be not serviceble and replaced with another unit.

Picked the car up and all was good for a couple of days and now the intermittent misfire is back....
I have not been able to get it back to be read but what is likely to be the problem.

There is no obvious oil in the loom... I have checked this at the rocker cover connection and ecu end.
The car is chipped with the big TRT chip and has an intercooler.

Also in the mornings the car hesitates and seems to not come on full boost, once the car is warm and switched off for a short period it is fine?

Faulty loom internally? ecu fault? faulty injector again?

Cheers

Giles

[Redback]

Oil in the injector harness would be my guess, common problem with TD5s

Baz.

[Blknight.aus]

on top of redbacks oil in the loom suggestion I will also suggest pin/socket connectors on the injector side of the loom not doing their thing properly.

[Lionel]

Any advice greatly appreciated.

I have a 2003/2004 defender 90. It developed an intermittent misfire that could often be reset by switching the car off for a bit. This degenerated into a constant misfire, this was diagnosed via testbook at rovatech as no. 5 injector not operating.

This was then removed and tested to be not serviceble and replaced with another unit.

Picked the car up and all was good for a couple of days and now the intermittent misfire is back....
I have not been able to get it back to be read but what is likely to be the problem.

There is no obvious oil in the loom... I have checked this at the rocker cover connection and ecu end.
The car is chipped with the big TRT chip and has an intercooler.

Also in the mornings the car hesitates and seems to not come on full boost, once the car is warm and switched off for a short period it is fine?

Faulty loom internally? ecu fault? faulty injector again?

Cheers

Giles

If the injector harness & plugs check out OK, I would be looking at the TPS (throttle potentiometer). My TD5 Defender had this problem while under warranty, and it caused exactly the symptoms you describe.

Cheers,

Lionel

[Frenchie]

I was also thinking TPS

[quaddrive]

Thanks for the ideas. There is no fault with the TPs logged and it was replaced a shopr while ago.

[fraser130]

If you have the cruise control mod fitted, and it still does it while using the cruise, that will rule out the TPS.

My money's on the injector loom, it's an easy, cheap fix as opposed to an injector, might be worth doing anyway depending on how old the car is etc.

Fraser

[quaddrive]

tested on testbook again and no. 5 injector is out of range again.

Got a new injector loom and fitted it in 20 mins and all seems well for the quick deive I took it on. I'll keep my eye on it.

Many thanks for the input. I was under the impression that the looms only failed once oil leaked out... not a trace leaking out and still looks like it was faulty.

Cheers