Thread: TD5 mis-firing and surging (i think)

Ok, so Saturday morning I disconnected, sprayed contact cleaner, waited for it to dry and reconnected every electrical connection I could find under the bonnet, including the earths and the ECU plugs.

When I first tried starting and running it, things appeared to be worse, so I gave up and went inside.

Sat afternoon I needed to go to shops, so I jumped in and fired it up and didn't feel the usual problem.

Yay it's fixed (or so I thought - should have known better)

Sunday went for a big drive in it with the family, couple hundred kms, to see if the problem came back and it did ...

For most of the drive it was great, but at the end I could feel the problem returning ... oh crap.

So it appears to be electrical related, but I'm not sure what I did that made it go away for a while ... I will now try slowly disconnecting a few plugs at a time and see what I can work out, but alas it looks like Landy will have to sit out my trip to Dubbo next weekend.

YouTube
this may not be problem but my 1999 was low on power and hopping
might be woth a look

As already suggested, poor earth will cause numerous issues and its reasonably common for the earth point just behind the neg post to corrode, come loose or break off.

Also I have had many a D2 TD5 where owners said it had a miss or rough idle "sometimes" and was actually a failed solenoid on one injector and engine was running on 4 cylinders.

I think one of the key points is that after disconnecting/wriggling the looms the problem was worse, then better.
Check the loom particularly where the injector harness leaves the main loom down towards the steering box and across the front of the motor.
Note also that all sensors can be disconnected from a TD5 without causing your symptoms.
The only sensor to cause an issue is the CPS. Usually because the loom has been subject to leaking FPR and become brittle.

And FYI my post you quoted was definitively the upgrade Chip/Map.

Originally Posted by DazzaTD5

As already suggested, poor earth will cause numerous issues and its reasonably common for the earth point just behind the neg post to corrode, come loose or break off.

Also I have had many a D2 TD5 where owners said it had a miss or rough idle "sometimes" and was actually a failed solenoid on one injector and engine was running on 4 cylinders.

Hi Dazza without hijacking this thread how many and how often you had an open cct solenoid on an injector?
I had this on my D2a Discovery and when I did some research couldn't find many who had either.
I ended up swapping out the solenoid from a good one but well used injector and had no more problems..but it seemed at the time this problem was rare.

Brad

Originally Posted by Bradtot

Hi Dazza without hijacking this thread how many and how often you had an open cct solenoid on an injector?
I had this on my D2a Discovery and when I did some research couldn't find many who had either.
I ended up swapping out the solenoid from a good one but well used injector and had no more problems..but it seemed at the time this problem was rare.

Brad

Not that often, maybe half a dozen a year, the odd one with a broken spring.

my thing was, sometimes people find it difficult to know if their TD5 is actually missing, calling it "running a bit rough, but once I get the revs up its fine" when in actual fact its running on 4 cylinders all the time.

Originally Posted by strangy

I think one of the key points is that after disconnecting/wriggling the looms the problem was worse, then better.
Check the loom particularly where the injector harness leaves the main loom down towards the steering box and across the front of the motor.

I should hopefully find time to look at this soon, i did have an initial look at this originally and didn't see much wrong with the wiring in that location, up past the injector connector, over the front of the rocker cover and past the exhaust, all the wiring is exposed directly to the heat, i will wrap this in wire wrap shortly (its on my "Landy to-do" list)

Originally Posted by strangy

Note also that all sensors can be disconnected from a TD5 without causing your symptoms.

Good to know, thanks for this info.

Originally Posted by strangy

The only sensor to cause an issue is the CPS. Usually because the loom has been subject to leaking FPR and become brittle.

CPS sensor was replaced by the mechanic which didn't fix my issues... $300 for naught

Originally Posted by DazzaTD5

my thing was, sometimes people find it difficult to know if their TD5 is actually missing, calling it "running a bit rough, but once I get the revs up its fine" when in actual fact its running on 4 cylinders all the time.

Does this show as a fault code in the system ? if yes, then that was already checked, no fault codes.

Anyone know someone in Sydney that good with td5s ?

I'm still having issues with this and I just want it sorted now.

I have checked and eliminated earthing issues and wiring that I can find, I have unraveled the injector wiring and inspected it. Now I'm guessing it may be ECU related ...

Anyone know where I can pickup a rewritable NNN ECU for reasonable price ?