Hi all! New here.

Got a Td6 some weeks ago,(02mod) not sure how smart that was, but it is a good looking car with lots been done to it over the years. It went thru the mot without any remarks, but the day after it would not start. The fault code says: "9F6 Fuel Pressure Monitoring wilst starting"

Have checked that diesel comes out of the filter normaly, but also checked that no fuelpressure. So then I assume the problem is the high pressure pump? A mechanic told me to try to start and at the same time pull out the connector to the fuelpressure sensor, because if it had started then, the fault should be the sensor, but it did not start, so I guess the fault is the high pressure pump, or the pressure regulator valve? Maybe some of the gurus in here have had the same issue?
Greetings from Oslo

Check the plug that goes to the rear of the fuel rail, they can get full of green muck and cause high resistance with no start, also check the secondary fuel pump is working, it is located under the rear floor passenger side UK about where peoples feet would be, under the vehicle there is a small flap held in place by two screws if memory serves me correct. If that pump is not running it will not start and show low fuel pressure. Happened on my TD6, was an intermittent fault pump kept sticking . Pump is easy to change and not expensive.

Thanks for reply, I know about the secondary fuelpump on the underside, but I have already checked by diconecting the fuel hose that goes from the fuelfilter to the High p pump, and I filled up a cup with diesel by swtching on the ignition in about 2 seconds or so, so I assume the pumps deliver diesel. The connector to the sensor looks fine also, thats why I think its the High p pump.? L322 Td6
LR 88 V8
Jaguar S-type V8
Triumph Tr8
Fiat 500

Difficult to throw any more light on that one to be honest, but I’ve not heard of a h.p pump failing before on one of those, it’s usually sensor, wiring or electrical pump. The other thing is an injector letting fuel return when it shouldn’t, you could try a leak off test by taking the leak off pipe off the top of the injectors and switch the ignition on (not start the engine) you should see no fuel spill or very little. Hope you get it sorted.

Yes I also find it strange that it could be the h pump from one day to another, think it might be an electric fault somewhere. A good thing that the high p pump is not a typical issue then. And yes I have read about the leak of test, think I will try that, Thanks! L322 Td6
LR 88 V8
Jaguar S-type V8
Triumph Tr8
Fiat 500

I suspect you have already googled this error and all the posts on BMW and RR forums go nowhere. You may well have low fuel pressure but that doesn't mean that the engine will not start. Crankshaft sensor, intermittent supply to injectors and so on could be the cause of the non start? I'm not suggesting if it was my car I would ignore that error but you have already tested good supply from the electric pumps and the HP pump is mechanical so I would first verify that the engine ECU is not disabling voltage to the injectors - unlikely in my opinion as I would expect to see an additional error code for this and for now move on to any sensors that would inhibit starting? I had massive leak off on most of my injectors on my TD6 and a previous Mercedes diesel with more modern Piezo injectors and it never prevented starting, just caused excessive smoke on idle Current: 2003 TD6 HSE. 161,000 miles
Previous 1993 Classic 3.9

Yes you`re right, I have read about this on other forums, and some have had similar issues and found out it could be the fuel pressure valve, and I have already removed the inlet mangfold and the valve, but really not sure if I had to, cause I cannot see any fault on the valve. It may be one of the things you mention Steve. Any relay or connections maybe? Sensors also, but the faultcode I have, Fuel pressure monitoring whilst starting? It means that there are no fuel pressure when I try to start? The mechanic I talked to told me to try and unplug the conector to the pressure sensor at the wery same time as cranking, if it had started then, it would have been a faulty sensor. He was kind enough to lend me a wery expensive diagnostic reader to check if there was any fuel pressure when starting, = no pressure.
But I really want to check the cause of this may be about any electrical faults. L322 Td6
LR 88 V8
Jaguar S-type V8
Triumph Tr8
Fiat 500

I can't help with any specific electrical checks as I have no experience with this problem. If the diagnostic tool was showing live data and zero pressure I would loosen an injector feed pipe and see if there is any high pressure fuel leaking out when cranking and go from there.

There is a solenoid on the rear of the high pressure fuel pump that is not easily accessible without removing the inlet manifold but you should be able to check for continuity upstream at the engine ECU and I have a spare solenoid it has two connections and it measures 2 Ohms resistance.

If the engine ECU is not seeing fuel pressure it may well be actively preventing an engine start for safety so not energising injectors or opening the high pressure regulator (the above solenoid) fully Current: 2003 TD6 HSE. 161,000 miles
Previous 1993 Classic 3.9

I had the same problem with my 03 TD6 a few weeks ago with the same fault code. I got under the car where the 2nd fuel pump is located and had my father turn on the ignition. I only heard the in tank pump running, then I knocked on the 2nd pump with a screwdriver and it started running but sounded unhealthy. This was enough though to start the car.
Changed the 2nd fuel pump after and never had the problem again.

Ok, gentlemen, you just gave me some more things to check out now. Before I put back the pressure valve, the one at the rear of the high pr. pump, is this what you call the solenoid? It should give a reading of 2 Ohm resistance? Have read that the small O-ring on the tip of it it can cause problems if its a little damaged. Guess I should have checked about the pump under the car before, but since I got diesel coming out of the filter, I assumed the pumps back there were fine. I also did check, before I dismantled anything, that diesel was coming out of the front diesel feed pipe, but could not see the power of the flow, since I was alone sitting in the car cranking, and I just saw that there was spilled some diesel around the pipe. L322 Td6
LR 88 V8
Jaguar S-type V8
Triumph Tr8
Fiat 500

Yes that was the item I was referring to. It is a solenoid in the way that it operates albeit with very precise control from the engine ECU. I can't remember how Land Rover or BMW refer to it, possibly pressure regulator. The O ring is apparently a known problem if it allows fuel to bypass. You need to get a copy of the RAVE Land Rover manual if you do not already have a copy as it contains everything about the car. It may be available to download from this forum somewhere., if not do a Google. Current: 2003 TD6 HSE. 161,000 miles
Previous 1993 Classic 3.9