[sparkymarky]

HI guys,

Ok so I have a fuel filter fault code.
Changed the filter. Performance noticeably increased immediately.
Cleared code.
Code reappears every time.


I have noticed there is no 'buzz' sound of any pumps priming when you turn the ignition on like when i first got the car....
But it starts, drives and accelerates great. Still this code though.

I have checked: the pump under the rear seat (drivers side). 10v present on the pump plug (from the fuel ecu above it) when you start the car (no volts at plug or from fuel ecu when just ignition only on). You can also hear this pump running with the rear seat up when the engine is running.

Is it this pump you usually hear prime when everythings working as it should be turning your ignition on? As i cant seem to find any other inline pump on this model....

Any ideas??


In fact could someone just turn their ignition on and confirm a priming buzz comes from somewhere?

[KM79]

Fuel filter code?What engine type is the car?

[sparkymarky]

Hi mate, its the M57Tu2..........e90 330d single turbo

so one pump in the tank, fuel filter under middle of car and then HPFP in the engine bay - no inline pump.

[KM79]

Yeah that's right ,the tank pump primes the hp one driven by the engine at a couple bar pressure.Whats this 'fuel filter' code?

[sparkymarky]

4587 'fuel filter' is the code...

[old grey steve]

Originally Posted by KrisM79

Yeah that's right ,the tank pump primes the hp one driven by the engine at a couple bar pressure.Whats this 'fuel filter' code?

indeed it does

Originally Posted by sparkymarky

4587 'fuel filter' is the code...

out of interest where did you get your fuel filter from?

We used to get fuel filters when we were stuck from Euro's/GSF I say stuck what I mean is when the local BM dealer hasn't got any and we saw an alarming set of issues that were quickly resolved by getting a filter from BMW, when you look at the filters closely side by side you'll notice that although both are manufactured by Bosch the diameters of the inlet outlets are a little different enough to effect things when under pressure and fuels flowing(therefore what's the score internally?)

Therefore we go genuine all the time unless pushed into a corner

[KM79]

Originally Posted by sparkymarky

4587 'fuel filter' is the code...

Ive never heard of that before.what kind of diagnostic gear is being used?

[davidjaen]

Originally Posted by sparkymarky

4587 'fuel filter' is the code...

You have the pre-heater where the filter is connected bad. Change it and that error dissapear.

[sparkymarky]

Is there some sort of strainer in the pre heater? Wow they seem expensive?!?!

[sparkymarky]

Originally Posted by KrisM79

Ive never heard of that before.what kind of diagnostic gear is being used?

INPA on my laptop... i think it assumes its the filter but its actually just seeing less pressure than it expects just before the high pressure fuel pump on the engine....it cant be down much though as it goes like stink straight after i changed the filter the other day.

[KM79]

Ah ok the filter heater,that makes bit more sense.They do fail right enough.Ive never looked inside one mate but it's just an electrical element to warm it up.

[KM79]

You would get a different fault code if the pre supply pressure was low.

[sparkymarky]

I thought i would get a 'pre supply low' code or something as you say...

poor design if if it is the plug in heater side which is being flagged up as the fuel filter....i'll get my multi-meter on the heater and see if there's voltage there...
in which case, do you know kris if its a permanent heater or temperature dependent?


Will this restore the fuel priming though? It'll just rid the code (which is great) as there will still be no voltage present from the ECU pins until the engine is cranked.... but if there's no code for low pressure and it starts fine then who needs the priming eh? (unless it knackers my HPFP lift pump after a while of course!)

[KM79]

It's temp dependant but I have no idea what temp it cuts in. What do you Mean by fuel priming?
The dde activates a relay to power the unit up.

[sparkymarky]

By fuel priming I mean that i'm sure i used to hear the pump buzzing either when you unlocked/opened the door or put the ignition to on.
I dont hear it anymore. Maybe i'm misremembering.
But surely on all cars the pump primes the fuel up the line briefly before starting.

I dont think mine does it.

The ECU/relay behind the back seat which feeds the pump in the floor (under the rear bench seat) only has 10v output to the pump when the engine is turned over. With a meter on the output pins and the keys at 'ignition' there is no voltage to the pump.... and so no priming at 'ignition on'...... i thought there would be....and that there used to be...?

[KM79]

Yeah the EKPS unit varies it's voltage depending on load required.Higher voltage at full throttle etc.Petrol cars prime on unlock but diesels prime on ignition on usually(there's many variants depending on engine/model).I can safely asume you're low pressure pump is ok otherwise you wouldn't get very far!

[sparkymarky]

Thanks Kris I can categorically say there is no voltage to the pump at ignition (i'm an electrical engineer, all be it Aircraft) but if you say i would have running probs then fair one - as i have zero starting or running probs.
So the priming musn't be an an issue and i'll leave it....

I'll just replace the fuel strainer heater...although it looks like its £200?!?!?!?!?!?! So i'll have a go at repairing it first

[Frobius]

Have you plugged it back in?

[KM79]

Originally Posted by sparkymarky

Thanks Kris I can categorically say there is no voltage to the pump at ignition (i'm an electrical engineer, all be it Aircraft) but if you say i would have running probs then fair one - as i have zero starting or running probs.
So the priming musn't be an an issue and i'll leave it....

I'll just replace the fuel strainer heater...although it looks like its £200?!?!?!?!?!?! So i'll have a go at repairing it first

Jesus,bit pricey!Forgot to say there was a recall on these too on some models .Worth checking in to.

[evo97]

Did you get to the bottom of this fault mate? Im getting the same fault and have replaced the fuel filter.

[sparkymarky]

Hi, nope I left it in the end so the code is still there. Not had any fuel problems in the cold over winter although it's been pretty mild. Be interested to see if you change it though!

[evo97]

Originally Posted by sparkymarky

Hi, nope I left it in the end so the code is still there. Not had any fuel problems in the cold over winter although it's been pretty mild. Be interested to see if you change it though!

Thanks mate. I will report back once fitted

Nathan.