What lights and behaviour do you get when it isn't starting?
I had a similar problem with a (new to me) TD5 over the summer which developed an intermittent starting problem. I'm new to all these electronics in a landy so I was on a bit of a learning curve trying to work out the cause.
My symptoms were that most of the time it would start just fine on first turn of the key with normal light pattern: turn key to position II, yellow ECU & glow plug lights come on and then go off leaving just alternator light on, temp gauge cold... crank and it started fine.
When it was failing there was a different pattern no yellow lights, just red alternator light, and temp gauge goes full scale deflection off to the right.
After a bit of reading around, I worked out that this pattern means the ECU isn't operating (the clue is that the ECU drives the temp gauge and both the yellow lights but not the red alternator light which is independent) so literally the lights are on but nobody is home.
Turning the ignition off and on again a few times until I got the usual pattern of lights would normally cure it, but on bad mornings this would take a few minutes before it eventually deigned to start. On just one or two occasions, just after starting, the yellow ECU warning light would come on briefly and the engine would momentarily misfire or die and then pick up again and continue as if nothing had happened.
Before finding someone with a testbook I decided to work on the hunch that as the ECU was completely shutting down perhaps it had a power problem so I swapped the 10A relay that powers the ECU and tightened the earth connection and the problem then went away. Big sigh of relief, expensive repair bill averted until...
A few weeks later on holiday in the lake district when problem comes back much more aggressively, engine cutting out half way up/down hills. At this point, convinced I now have a half dead ECU I try a last ditch repair before getting it trailered to the local dealers for a wallet transplant in their favour of buying a kettle lead from a local shop, dismembering it to get some wire out and running a direct earth trace from the ECU earth connection to the battery negative terminal. Problem completely gone away!
In fact this reminds me that said kettle lead remnants are still there several months later and I really must tidy this up with a proper earth strap onto the gearbox or something.
What lights and behaviour do you get when it isn't starting?
I had a similar problem with a (new to me) TD5 over the summer which developed an intermittent starting problem. I'm new to all these electronics in a landy so I was on a bit of a learning curve trying to work out the cause.
My symptoms were that most of the time it would start just fine on first turn of the key with normal light pattern: turn key to position II, yellow ECU & glow plug lights come on and then go off leaving just alternator light on, temp gauge cold... crank and it started fine.
When it was failing there was a different pattern no yellow lights, just red alternator light, and temp gauge goes full scale deflection off to the right.
After a bit of reading around, I worked out that this pattern means the ECU isn't operating (the clue is that the ECU drives the temp gauge and both the yellow lights but not the red alternator light which is independent) so literally the lights are on but nobody is home.
Turning the ignition off and on again a few times until I got the usual pattern of lights would normally cure it, but on bad mornings this would take a few minutes before it eventually deigned to start. On just one or two occasions, just after starting, the yellow ECU warning light would come on briefly and the engine would momentarily misfire or die and then pick up again and continue as if nothing had happened.
Before finding someone with a testbook I decided to work on the hunch that as the ECU was completely shutting down perhaps it had a power problem so I swapped the 10A relay that powers the ECU and tightened the earth connection and the problem then went away. Big sigh of relief, expensive repair bill averted until...
A few weeks later on holiday in the lake district when problem comes back much more aggressively, engine cutting out half way up/down hills. At this point, convinced I now have a half dead ECU I try a last ditch repair before getting it trailered to the local dealers for a wallet transplant in their favour of buying a kettle lead from a local shop, dismembering it to get some wire out and running a direct earth trace from the ECU earth connection to the battery negative terminal. Problem completely gone away!
In fact this reminds me that said kettle lead remnants are still there several months later and I really must tidy this up with a proper earth strap onto the gearbox or something.
