Thanks for your reply

Only thing left to replace is fuel pump and full assembly. maybe there's a check valve build into the top of the assembly.

There's nothing else which I can see which would allow pressure to drop so fast back to tank. :-/ as everything else has been replaced and no signs any leaks 2003 Range Rover 4.4 Litre V8 - Adriatic blue

2003 Range Rover 4.4 Litre V8 -Maintenance History Click Here = http://www.fullfatrr.com/forum/topic39687.html

I know you've checked the coolant sensor, but have you replaced it? (I'm tempted to try that one myself, not very expensive). Current: 2004 Vogue 4.4 V8 - 2004 Discovery 2
Previous: 2000 P38 DHSE - 1995 P38 DT Man - 1990 3.9 SE Classic, 1980 3.5 Classic 2dr

it may well be the coolant temp but when i checked the Code reader live data it read correctly for mine. but let me know if this fixes yours

i don't really want to spend £350-400 for full fuel pump / assembly.

so i am going to install a check valve after the fuel pump in the fuel line. to see if this fixes the issue.

i will post the outcome just need to order one and arrange day i am free to fit. 2003 Range Rover 4.4 Litre V8 - Adriatic blue

2003 Range Rover 4.4 Litre V8 -Maintenance History Click Here = http://www.fullfatrr.com/forum/topic39687.html

It amazes me that this seems quite a common problem (even across the BMW forums) and yet no one seems to have a definitive answer.
I can't see anything within the full pump that would want me to buy the full assembly. The actual pump I bought was a pieburg so original.
I'm away at the moment so will have a look when I get back after the weekend. I'll get a temp sensor from Land Rover so I can rule out cheap copies. Current: 2004 Vogue 4.4 V8 - 2004 Discovery 2
Previous: 2000 P38 DHSE - 1995 P38 DT Man - 1990 3.9 SE Classic, 1980 3.5 Classic 2dr

I discovered that my warm start issue was actually caused by the LPG system. The diaphragm in the reducer was worn and was allowing gas to fill the manifold after the car was turned off, this would slowly leak away if left for long enough. I replaced the seals in the reducer and it's now perfect.

I'm not sure about b348xyx, but I'm not lpg - just purely petrol. Current: 2004 Vogue 4.4 V8 - 2004 Discovery 2
Previous: 2000 P38 DHSE - 1995 P38 DT Man - 1990 3.9 SE Classic, 1980 3.5 Classic 2dr

thanks for your update jacckk and glad you got yours sorted

and yes lenb mines just petrol no LPG on mine.

I have some parts coming today will post outcome when fitted. 2003 Range Rover 4.4 Litre V8 - Adriatic blue

2003 Range Rover 4.4 Litre V8 -Maintenance History Click Here = http://www.fullfatrr.com/forum/topic39687.html

FIXED !!!! starts perfect every time now !!!!


Installed a check valve (Sytec Motorsport One Way Valve For Fuel 8mm Push On In Black - OWVS008-BK) just after the fuel pump on the hard plastic fuel line. (blue line)

theirs not much room in the to work, but heat gun to loosen the plastic pipe up and push the fuel check valve in the line.. hose clamp tightly after... some swear words later..

Fixed my issue, so my new fuel pump either has a bad check valve or the Assembly has bad check valve somewhere.

The fuel pressure is staying as it should now as well no fuel pressure lose over time.

So after buying Crank Sensor, Cam Sensors and refurb injectors its could been fixed with a £12 check valve ! oh well as least car has lots new parts ! and to be fair the car is running nicer with the new injectors anyways.

hope this helps someone else out there.

Sounds good to me

Would love to know the reason why it's worse when hot though - just so I can get my head around it. Current: 2004 Vogue 4.4 V8 - 2004 Discovery 2
Previous: 2000 P38 DHSE - 1995 P38 DT Man - 1990 3.9 SE Classic, 1980 3.5 Classic 2dr

heat from engine helps push the fuel back down the pipes ?

or ECU gives engine more fuel faster when cold ?

god knows but tested starting 30mins, 2hours, 1hour and starts perfectly every time now.. just like it use to so i am happy with that. 2003 Range Rover 4.4 Litre V8 - Adriatic blue

2003 Range Rover 4.4 Litre V8 -Maintenance History Click Here = http://www.fullfatrr.com/forum/topic39687.html

heres a video after car been left sitting for an hour after 20mins drive to get car to temperature.

Starts like it use to now.

With non return valve fitted and starting normal.






Below without non return valve.

 2003 Range Rover 4.4 Litre V8 - Adriatic blue

2003 Range Rover 4.4 Litre V8 -Maintenance History Click Here = http://www.fullfatrr.com/forum/topic39687.html

Going to get a valve ordered 😀 Current: 2004 Vogue 4.4 V8 - 2004 Discovery 2
Previous: 2000 P38 DHSE - 1995 P38 DT Man - 1990 3.9 SE Classic, 1980 3.5 Classic 2dr

I have exactly the same "hot start" problem and have fitted one of these valves in an attempt to cure the problem but it hasn't made a difference.
Should the live feed to the fuel pump be +12 volts all the time the ignition is "on" or only when the engine is being cranked over on the starter and then when engine is running ?
On my car, the feed to the pump is not live on the ignition switch but seems to become live when the engine is cranked.
Cheers
David 2002 4.4 V8 with LPG
Zambezi silver