mattstevenson2005 wrote:

does any one know a way of testing the fuel pump to make sure that it is this that is causing the issue? - just looked at the price and they are VERY expensive - although i could use a modified X5 part if the worse comes to the worse.

Matt

Hi Matt,

I am a Motor vehicle lecturer at Belfast Metropolitan College, I posted earlier on in this thread.

I would be very reluctant to change your fuel pump at this stage without independently checking it.

I think you may be at point now were you don't know what to look at next, and may start changing costly items which may not cure the fault. Your best bet is most likely to find a GOOD independent specialist.

If you can find a diagnostic guy who is good with oscilliscopes such as the Picoscope he can test your crank sensor, temperature sensor, injector pulse etc to see whether they are operating as they should. He should be also be able to carry out a independent fuel pressure test, to check whether your fuel pump is working correctly thereby possibly saving you money.

Testing the sensors as I described above is easy when carried out by a skilled operator, does not require dismantling any component, and will guarantee that each sensor is working correctly. The time taken to do the fuel pressure test and check the 3 items above using a dedicated oscilliscope believe it or not should only be around one hour!

If you do go down this route choose the guy carefully, he must specialise in electrical diagnosis.

Hope this is of some use.

Stephen

Totally agree with the use of the Pico scope, There is no point in just throwing parts at it in the hope that it will be fixed. I use a Pico scope and a snap on solus pro together and got all my engine data scoped and saved on a computer so i know what good waveforms are.
I see a lot of it could be this it could be that but in reality its usually none of them.
What needs to be done is the cam and crank sensors need to be scoped and the fuel pump pressure and amp draw need to be checked first.

rgds  do or do not there is no try.....

Matt,
Did you ever get to the bottom of this? Mine does exactly the same since I changed the fuel pump out...

no im still trying to find others that have had the same problem and have solved it

Matt

Hy Matt,

Did you get to the bottom of this at all..?

I have exactly the same problem as yours.I replaced the fuel pump in mine recently after it failed.We picked up a bmw pump and stripped down/rebuilt my rangie one with the new pump.We tested the new pump before doing it so I know it was working fine before putting it in.I'm just wondering have I a blocked filter now as well.

Anybody got any advice on changing the fuel filter on a petrol V8,its a pain to get at the clips..!!!

kind regards

Richie