This LRO reader emailed LRO.firstname.lastname@example.org to ask our experts why his Defender is so jumpy in the wet.
My Td5 110 starts to cut out in heavy rain, lunging along as if someone is turning the ignition off and on. what do you think is wrong?
Derek Savill, Romsey, Hampshire
As the problem only occurs in heavy rain, that suggests water is entering the main wiring loom to the engine ECU or the ECU itself (which is located beneath the driver's seat).
Check under the seat to see if the area is wet when the problem next occurs. The loom runs under the vehicle, across the gearbox and into the area under this seat.
Sometimes the rubber grommet through which the loom passes is damaged, or even missing. This can lead either to water ingress to that area or the loom rubbing on the metal edge of this underseat box - again leading to water contamination.
This workshop advice appeared in the April 2016 issue of LRO. Back issues are available to download on digital devices here.