I've had a few cars but never before a car that even the dealer cannot fix.
The first issue is a strange droning noise at low speeds (30 to 50mph), which they can't diagnose. It doesn't affect the running of the car though but is quite annoying, and will affect selling the car in the future.

My main issue though is with the automatic lowering of the suspension and engine slow down. The problem started on our way back from France whilst towing our caravan. Luckily, after 2500 km, we made it to Dover before the problem occured . We got towed back to London and I took the car to my local LR dealer (Lookers in Park Royal) the next day. They diagnosed a faulty break switch and a failed coolant bottle sensor. £350 and i was back on the road...but not for long. a 100 mile round trip and the problem reappeared. Took the car back to the dealer and this time they replaced the fuel filter. £150 and back on the road...but again not for long. A 50 mile round trip and problem reappeared. Took the car back to the dealer and this time they suggested i replace the fuel pump at a cost of £850!
Needless to say, I'm not prepared to replace every component on the car until they fix the actual problem.
I've read a few threads and to be honest I'm none the wiser. Problem clears itself once i stop and restart the engine so most likely some electricl glitch. Any suggestions would be much appreciated, and if someone could recommend a LR guru around London, that would be great.
The car is a LR3 2007, 147K. Thanks.

 

I don't know alot about LR3's, but I know that replacing a brake switch, coolant bottle, fuel filter and fuel pump will not fix a SUSPENSION problem.

Sounds like bad height sensors. You may get better info on LR mechanics in London on a UK specific site.

 

Thanks for that. Suspension actually works fine. but I'm going to check if there are any leaks by removing fuse F3 and checking results after a couple of days.

 

What engine do you have?

Are the symptoms the same now(needing a fuel pump) as they were before(needing the brake light switch)?

 

Can you elaborate a bit on the lowering of the suspension and what all the car tells you in terms of lights, icons, messages, etc?

The droning noise could be wheel bearings or differential.

Not sure about the engine slow down part. Could be a lot of things but commonly MAF Sensors and Throttle Bodies have needed R&R.

 

Hi. Yes, the symptoms are exactly the same. The only time I got a relevent error message was with the coolant liquid bottle. The only thing I would add is that the issue conly occurs once now and doesn't reappear for a while after restarting the engine. Before the fuel filter replacement, I'd have to do this stop/start process 3 or 4 times.
Thanks for the interest in my issue.

 

What engine do you have?

If the dealer read the faults, and diagnosed it as a failed brake light switch, and symptoms did not change, I would start by checking your brake lights, both that they're working(with headlights turned on and off) and that they're the same brightness side to side. A bad ground in the bulb socket(very common) will backfeed voltage and mimic a brake switch failure, which can give all the symptoms you have listed(at least on a US spec vehicle, but I assume you have a diesel as the gas models don't have a fuel filter to replace)

Do you have daytime running lights engaged?
Does the happen only when the lights are switched on?

 

Hi Dave and thanks for the advice.
The car is a 2.7 TD V6.
I'll check the break lights tonight and report back.
I have the lights set on automatic so they come on as and when the light level is low.
The problem has happened both with lights on and off.

 

Hi Dave. Tried the break lights in all light settings and there's no difference in intencity from one side to the other, or the top.

 

Well simple and easy(even though often overlooked) fix is a no go then.

At this point kind of need the fault codes, in all modules, and probably some time looking at various inputs.

Have you noticed any water in the vehicle? wet floor boards up front?