3.9efi electrical problem.

My Disco has the annoying habit of losing power if off roading, especially if climbing slopes, it then struggles to tick over for a few minutes, then its back to running perfectly until you try steep climbs of very rough ground again!
I thought it was a fuel problem and replaced the fuel filter and even the in tank pump, but I've now noticed that when it loses power it loses electrical power as well.
I had the radio on and noticed it stopped momentarily, it transpires that the vehicle loses electrical power, stalling the engine.
When I'm on the road its perfect, doesn't miss a beat, so I can only assume its either a broken wire or bad connection.

Anyone else had a similar problem? As there is nothing obvious and it will be like looking for a needle in a haystack trying to trace a broken wire.

Thanks in advance

Ian

Interesting fault you have there, sounds like it could be an ign feed problem. Get a wiring diag and look for common feeds for the items showing a problem then rig up test lights at various points on that circuit and drive accordingly to cause the fault.

A leccy problem like that will probably have you tearing your hair out but when you finally cure it you'll be cursing because it will be something simple or stupid!

Anyway, I think first thing to check is alternator output, a weak alternator will cause what feels like a mis-fire, most notable when there is a high electrical load and you give it a bootful.

Next I would say check the wires and connectors to the coil - the wires corrode as do the connectors, make sure all is clean and tight.

Remove and clean the main earths and also clean the battery terminals and cable connectors, smear with vaseline and put the leads back making sure they are tight.
HTH

Many thanks for the advice, a few jobs for boxing day then.