2003 X5 Diesel [Australia] heat related issues?

[thelostboss]

I have a 2003 diesel X5, recently purchased with 400K plus on the clock but well maintained. It runs really well except when in stop-go traffic in hot weather conditions and has had occasional reluctance to start on first turn of the key when it has been run for a while. Yesterday however it became much worse. Car had been driven for around 190 km on a day of temps in the high 30s [celsius] when it threw a low coolant warning, coolant level when checked was fine. On the return journey it first gave a "check oil level" warning, followed some time later by a "low oil pressure" warning. The oil level was checked and was fine. These warnings only appeared when stationary and shifting to neutral cleared them from the display. The car was then parked for around 15 minutes and at that stage it would turn over but would not fire. I happened to be outside a Mercedes mechanic at the time and he plugged in his computer [despite being officially closed at that time], the only error showing was related to "fuel rail pressure" - I did not see the display and so cannot be more precise than this. After around another 45 minutes cooling-off it started perfectly as if nothing had happened at all.


I am thinking that it might be an electrical heat-related issue with one of the ECUs [coming from a Land Rover background] or possibly fuel pump or injector related.


Any suggestions would be gratefully received. I have ordered some diagnostic software and cables in order to set up my own diagnostic system, but that will not be here for some weeks; and summer will be here before then!


Cheers
TLB

[wpoll]

Wow - where to start...?

There are literally dozens of failures that could cause what you are seeing and there's not a lot of diagnosis you can do without the tools you have on order. Maybe you can find another local member there who has some kit? Where in Aust. are you?

I guess a simple first step is next time this happens, listen for the fuel pump under the rear seat when you turn the ignition on. You should here it whirring away for about 10 seconds. It may not do it if the ignition was only just switched off but it should do it after 15 minutes or so. This is the in-tank electric fuel pump - the first of three fuel pumps feeding diesel to your engine.

The second pump is an inline electric pump under the car, looks like a filter but it's an electric pump.



The third pump is the mechanical HPFP mounted on the engine - not something you can likely test or want to goof with.

Eliminating the first two as issues will be a good start but given the intermittent nature of your problem it might be frustrating!

Good luck!

[andrewwynn]

Electronics definitely can fail intermittently when gets hot. Make sure your ebox fan is working. I don't know if there is a temp sensor in there so you could put a remote thermometer in there to see how hot it gets.

[wpoll]

Originally Posted by andrewwynn

Electronics definitely can fail intermittently when gets hot. Make sure your ebox fan is working. I don't know if there is a temp sensor in there so you could put a remote thermometer in there to see how hot it gets.

FWIW, there are ebox fan differences between the earlier M57 diesel (pre-facelift) and the later M57TU (facelift) cars.

In the M57 version, using the DDE 4.0, the ebox fan is controlled by a thermo-switch (B6235).



In the M57TU cars with DDE 5.0 the ebox fan is controlled directly via an output on the DDE, presumably using some internal temp sensor within the DDE.

I mention this difference as I'm not sure which version car thelostboss has - a 2003 could be either the M57 or the M57TU.

[thelostboss]

Thanks for the replies so far.
I am located in Victoria on Philip Island and the engine is shown as an M57 when decoding the VIN.


Cheers
TLB

[wpoll]

Originally Posted by thelostboss

Thanks for the replies so far.
I am located in Victoria on Philip Island and the engine is shown as an M57 when decoding the VIN.


Cheers
TLB

So that would mean no xDrive, the 135kW engine and the primary fuel filter is under the hood/bonnet (and not under the car). Makes chasing fuel issues a little easier.

With any fuel rail presser related faults, I'd first replace the fuel filter if it hasn't been changed recently.

Here' an interesting read on the fuel system - it references the M47/M47TU, the four-cylinder version of our six-cylinder M57/M57TU engines.

http://www.londonroadgarage.com/imag...04-03%20kw.pdf

[thelostboss]

At last I have some diagnostic error codes to work with from the Carly app, codes as follows;


Engine / Motor
Fault Code: 0009F6 Fault Explanation: RaildruckUeberwachung the Start
Fault Code: 000404 Fault Explanation: Abgasrueckfuehr control
Fault Code: 003505 Fault Explanation: Glow


Instrument cluster / Kombiinstrument
Fault Code: 0000BD Fault Explanation: :EBV


Light / Licht
Fault Code: 00000D Fault Explanation: Diagnostic line U12 / 2 faulty / Report redundant inputs contradiction / Lambda probe heating before KAT / PowerMOS status line 2 always active


Aircondition / Klimaanlage
Fault Code: 00000A Fault Explanation: :10 free / Blower output stage or fan motor / AUC sensor / Mixing valves engine fault / Info Mixed air sensor 1 / Fresh air damper motor IHKA / Innenfuehlergeblaese / Water valve left / Relay auxiliary fan / Program switch potentiometer


Gateway /ZKE
Fault Code: 0000FF Fault Explanation: :unknown fault / BFS backrest head: blocking back / Unknown error


These of course mean nothing to me at this stage of my BMW education and so I am hoping that someone can shed some light on any or all of them.


Cheers and best wishes


TLB

[wpoll]

Originally Posted by thelostboss

At last I have some diagnostic error codes to work with from the Carly app, codes as follows;


Engine / Motor
Fault Code: 0009F6 Fault Explanation: RaildruckUeberwachung the Start
Fault Code: 000404 Fault Explanation: Abgasrueckfuehr control
Fault Code: 003505 Fault Explanation: Glow


TLB

These engine codes are the only relevant codes regarding your engine fault - the others aren't terribly important, i.e. the EBV code is very common and maybe be benign etc.

The first code (09F6) is "DDE: Rail-pressure monitoring on engine start"

The other two are: -

0404 - DDE: Exhaust-gas recirculation
3505 - DDE: Glow-plug system

BTW, DDE is "digital diesel electronics - the engine management system - yours is a DDE4.0.

The EGR and Glow Plug fault are unlikely to to be the cause of your fault, although they need fixing, while the rail-pressure monitoring IS relevant. Looks like you may have a bad fuel pressure sensor, perhaps one that is failing when it gets hot.

It's a start....(or not, sometimes, in your case! )

[wpoll]

Oh yeah, clear all the codes then see what returns. A few of the codes you mention will not likely be currently present but are historical.

For instance, the code "0D" is actually a very general code - "LCM: Light Check Module: fault stored" so ignore the bit about the Lambda probe heating - it's a red herring.

The FF code is "GM: Front passenger backrest upper section servomotor: Locking when moving backwards" - perhaps the seat was being moved and got jammed against luggage etc. in the back...