So the 90 broke down again, with a mystery!

Unplugging any sensor makes the ecu to go into presets aka limp mode.....
Unplugging your maf just makes the ecu fire in as much fuel as it can at per rpm point.
The car is misfiring and won't rev and its a diesel.
It's not going to be valve timing, its not compression so that leaves just fuel. Like the dealer said. From reading what you've said and not seeing the car personally I still agree with their original diagnosis.
Sand is sand. Sand in places where tolerances are fine not surprisingly ****s them up big time. Aka injector pump and injectors.
You can think of water, you can wonder how it happened you can unplug and test a million other things but its not going to change the fact that your injector pump has sucked a **** load of sand and pumped it through.

In regards to people saying the engine is too complex to be fixed in a desert....go buy a TDI THEN! Duuuuh.

I understand what you are saying, but what I dont undesrstand is how sand gets through the filter, a filter designed to filter out particles much much much smaller. I have conceded to the issue being fuel related, and as stated previously many times I cannot afford the proposed fix right now, so there is no harm in trying other things that are not costing me money.

I'm also a little confused that if in limp mode the pump will pump in more fuel but somehow cannot when not in limp mode? (is that what you are saying? if so/or not can you please explain so I can try and understand?)

Quote:

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Originally Posted by Leroy_Riding

I understand what you are saying, but what I dont undesrstand is how sand gets through the filter, a filter designed to filter out particles much much much smaller.....

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Filters are not sieves. Filters have an efficiency curve. At any given size they will remove a % of the particles. That may be 99.999% but if you dump an "ice cream cup" of dirt in a tank that may be 10^30 particles. At 99.999% efficiency, 10^27 particles will still get through the filter!!!

I have already posted previous research on here that shows in off-highway applications the filters on commonrail diesels do not meet specs.

Everyone should be aware that fuel cleanliness is very important for injector and pump life. A lot of pump diesel does not meet the required specs (which are pretty lax anyway).

The attached presentation from Cummins Filtration (Fleeetgard) may be of interest. Especially the "Tale of two mines" part.

EDIT: Also attached is a presentation from Donaldson (world's largest filter manufacturer) which shows how much dirt is allowable in pump diesel THAT MEETS SPECS!!!.

volume of sand is going from what the dealer told me, I only saw a sample of this (a few grains in a small container of diesel) but I trust my dealer.

so what I am hearing here is that chances are it is the pump and injectors not the VCV?

I will definatley invest in fitting some more inline filtration, provided this wont adversely affect my cars performance (once it is going again that is)

Ive been keeping abreast of this thread, and it seems to be the concensus that the problem is sand and water ingress into the fuel tank.

With my new 90 on its way, should there be a mod I can do straight away to avoid this problem without voiding my warranty? Another inline filter? Moving the breather?

Im sorry you have had to endure this trial but it may serve as a warning to others....

(My whole lifes only worth may very well just to be a warning to others.....)

Thanks for sharing it all.

JB.

the problem seems to be fitting something that wont void warranty as well...

Quote:

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Originally Posted by incisor

the problem seems to be fitting something that wont void warranty as well...

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so far from what I have read and been told by dealers is that any work done by a non qualified mechanic will void warranty (not speaking about anything in particular so not sure the validity of that comment)

and any modifications to anything voids the warranty of that system.

so I assume adding another filter inline is 'modifying' the fuel system therefore voids warranty on the whole system?


Leroy

So the options are to run it stock then have the dealer treat you like a criminal if something goes wrong, or make it fit for purpose and void your warranty.

Quote:

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Originally Posted by JamesB71

So the options are to run it stock then have the dealer treat you like a criminal if something goes wrong, or make it fit for purpose and void your warranty.

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I don't think that is quite the case, If you got an independent specialist to fit it maybe it is okay, but fitting yourself is a no-no? or have your dealer fit/make the changes then one would asume it has to be okay?? call your dealer and ask them as each dealer may have a different opinion. . .

Leroy

Quote:

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Originally Posted by Leroy_Riding

so far from what I have read and been told by dealers is that any work done by a non qualified mechanic will void warranty (not speaking about anything in particular so not sure the validity of that comment)

and any modifications to anything voids the warranty of that system.

so I assume adding another filter inline is 'modifying' the fuel system therefore voids warranty on the whole system?


Leroy

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Most of that is incorrect...

For starters have a look here (start at 4:45).
[ame=http://www.youtube.com/watch?v=qBISqS9oNB4]BUY NOW PAY FOREVER | Ep 1 | The Checkout | Thursdays, 8pm on ABC1 - YouTube[/ame]

Back on your problem - apologies if I have forgotten the key points over the last week. Did they give you the dirt yet? Where was the dirt found? in the tank or elsewhere?

I think you need to put this back on LR. If your vehicle has been used for normal use and only filled up at servos...