I have a couple of problems with my 2001 Discovery 2 TD5, that's covered around 70,000 miles. When I try accelerating hard, the engine ‘hesitates’.
At normal acceleration, there is no hint of a problem.
The second problem occurs when driving at about 60mph – there is a vibration, possibly from the front. The vibration eases when driving faster and appears to disappear altogether at about 70mph or so. Jim Ellis, Staffordshire
With regards to the hesitation, there are two things that could be checked/changed by you. The first is the fuel filter, ensuring you fit a
good quality part. I once had a customer who fitted an aftermarket fuel filter that was quite a well known brand. After around a week of the vehicle starting and stopping intermittently, we tracked it down to the filter. As soon as we fitted a genuine one, the fault vanished.
Otherwise, disconnect the engine electronic control unit connectors (located at the rear of the battery box) and check them for oil contamination. If there is any sign of oil in the red connector around the connector holes and the ECU plug you will have to remove the ECU lid and clean it with a solvent spray. Clean the connector and socket at the ECU end of the loom and replace the injector harness inside the cylinderhead.
If this does not rectify the problem, then I would recommend you take the vehicle to a Land Rover Specialist for diagnostics to be carried out.
Regarding the vibration problem, look underneath and check that the propshaft universal joints do not have any play in them and that there are no bolts missing from them. If these are all as expected, then have your wheels checked for balance. The speeds you mention equate to the frequency that wheel vibration can occur. If the vibration can be felt through the seat and floor, then chances are it is a rear wheel out of balance; if you experience a vibration on the steering wheel and some scuttle shake, this indicates that it's the front wheel that's out of balance.