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The E46 fitted with the M47N engine has 3 fuel pumps:

  • In tank
  • Intermediate, under the floor under the left-hand side front seat
  • High pressure, on the engine

I've replaced the fuel filter and intermediate fuel pump on the 320d, and now it won't start.

I've documented a problem where the car just cut out while driving and thought I had tracked this to water passing a bulkhead grommet and shorting a relay (or similar) - having removed most of the car interior to check the initial suspect, the heater element, and finding it wasn't the problem, then refitting everything, the car ran beautifully. For a while. Then it died, exactly as it did before. Checking showed everything to be dry.

I acquired a BMW Scanner 1.4.0 from another forum member (my apologies - I don't now recall who) and this revealed a code:

 - 4B90/11 - Rail pressure monitoring at engine-start

Further investigation reveals this is a code given when the intermediate pump fails. The in-tank and high pressure pumps are diagnosed with specific codes of their own; the intermediate pump doesn't do this.

I've replaced the pump and the fuel filter - no point just doing the pump. I even replaced them in the correct order - it looks like this may have been done before as they were the wrong way around. Probably not an issue, but let's do it properly! I've followed all documented procedure to ensure fuel flow through the pump and filter and there is diesel flowing from the front end of the pump/filter installation - next stop is the high pressure pump.

Engine turns over, but will not start.

Remove the inlet manifold, crack the connections to the injectors, turn the engine over for 10 seconds. Some fuel appears, but not as much as I would expect? Reconnect anyway, try again - no start.

There's then a hiatus due to my unemployment while I struggle to acquire a laptop capable of connecting sensibly to the Scanner... Windows 7/10 devices don't much like doing this. OK - got that sorted, installed software.

Check codes - there are no DDE-related (Digital Diesel Electronics) codes. No engine-related codes at all.

I have INPA software but don't appear to have the correct USB cable/connector arrangement. I was sure I did, but maybe I dreamed it? Loaned it to someone? Just haven't found it (again)? [Note to self - tidy the bloody garage!] I appreciate INPA is far more comprehensive than Scanner 1.4.0.

What I would like is for someone who knows what they are doing (I'm good at working things out, but start from a short-of-knowledge position) to come and give me a hand. It's a great car, and it is so frustrating to get this far without success. 😢 

Compensation for putting up with me is obviously available. :) Beersies, food, fuel money...

Pretty please? Someone...? 

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Checked compression using the rudimentary technique of blocking the inlet while cranking the engine - remove the obstruction showed a huge 'suck,' so compression looks to be good.

Wondering if the starter motor is a bit tired, but it certainly turns the engine over fast enough for it to start.

Problem is almost certainly after the mid-pump I installed, but as said - there are no errors indicating an HP pump issue. No DDE-related errors whatsoever. 

I'm going to try following the instructions in the attached doc, but does anyone have any suggestions for a home mechanic?

M47 DIESEL DIAGNOSIS GB-13-004-03 kw.pdf

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I'm happy to come down and help.

I just don't have the knowledge on the diesels, so hopefully someone can chime in with some advice, or some troubleshooting.

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Have you plugged it into a proper tool like DIS (such as in that pdf)?

What type of diagnostic port does it have, round pac-man or the square-ish one?

 

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19 minutes ago, M3AN said:

Have you plugged it into a proper tool like DIS (such as in that pdf)?

What type of diagnostic port does it have, round pac-man or the square-ish one?

Square connector.
I suspect I will have to invest more of my no-income in a cable that will work with INPA- the lead I have  came with and works with the BMW Scanner v1.4.0.

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Hmm, well I have INPA and DIS but my cable has the round connector using ADS as the interface.

If somebody has the appropriate converter then perhaps we can sort something out?

Alternatively, I still have the one you gave back to me, did you try that on the diesel in the end (http://www.bavariantechnic.com/modelfeaturematrix.aspx)?

 

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52 minutes ago, M3AN said:

Hmm, well I have INPA and DIS but my cable has the round connector using ADS as the interface.

If somebody has the appropriate converter then perhaps we can sort something out?

Alternatively, I still have the one you gave back to me, did you try that on the diesel in the end (http://www.bavariantechnic.com/modelfeaturematrix.aspx)?

I have a USB->square plug, and a square plug->round plug adaptor. <sigh>

I didn't try your kit on the car - didn't want to use up the chassis number allocation. And... Didn't htink I needed it because I thought I'd fixed the problem! Lol

I'll talk to Mrs M about investing in a USB->square plug cable for INPA.

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3 hours ago, zero said:

I'm happy to come down and help.

I just don't have the knowledge on the diesels, so hopefully someone can chime in with some advice, or some troubleshooting.

You don't need an excuse! Come down, offer moral support, suck teeth... ;)

Food will be supplied. 

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5 minutes ago, gjm said:

I have a USB->square plug, and a square plug->round plug adaptor. <sigh>

I didn't try your kit on the car - didn't want to use up the chassis number allocation. And... Didn't htink I needed it because I thought I'd fixed the problem! Lol

I'll talk to Mrs M about investing in a USB->square plug cable for INPA.

Cool... but please don't assume the USB->Square will work with my setup because mine is configured to use the RS232 port and I'm loathe to muck around with that. It may however be suitable for other, USB-based INPA/DIS setups.

If you run out of options and think that other kit I have might be of use I won't need immediate payment FWIW.

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1 minute ago, M3AN said:

Cool... but please don't assume the USB->Square will work with my setup because mine is configured to use the RS232 port and I'm loathe to muck around with that. It may however be suitable for other, USB-based INPA/DIS setups.

If you run out of options and think that other kit I have might be of use I won't need immediate payment FWIW.

Thanks bud. Very much appreciated.
I shall shortly have use of a shed to work on cars (assuming I don't get a job on the other side of the country and move!) so it'll be full steam ahead.

 

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good luck with it.!And the job hunting!

 

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usb sucks.

acquire an old win xp laptop with a serial port, if only you knew someone with an abundance of them ;) and connect using that. alternatively, icom's are a possibility, though i do not have one.

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@_ethrty-Andy_ USB itself doesn’t suck, it’s normally the sub par USB to serial adaptor.

I almost got something working on my windows 10 laptop over USB, I only stopped because I didn’t know how to use the software so couldn’t test properly.

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1 hour ago, eliongater said:

@_ethrty-Andy_ USB itself doesn’t suck, it’s normally the sub par USB to serial adaptor.

I almost got something working on my windows 10 laptop over USB, I only stopped because I didn’t know how to use the software so couldn’t test properly.

W10 can require BIOS changes (certainly needs specific USB port config) in order to work properly with many diagnostic cables.

I've been given an old(er) Compaq Presario V2000 running WinXP. No serial ports, but haven't had an issue with the USB and Scanner 1.4.0 (so far).

The real test will be if it'll work with a 'proper' cable and INPA.

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No serial port = no ADS. Period. ADS uses a specific hardware address that can not be mapped to USB. INPA and DIS use ADS.

ADS is the only protocol that allows access to all modules. But you may not need all modules so USB alone could be fine, especially if you can activate individual components.

If you can find a docking station for that Presario that has a serial port that'll probably work. My HP laptop doesn't have a serial port but the docking station does and that works just fine with INPA/DIS. Version of Windows doesn't matter either, it just has to be 32bit.

 

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Nothing is ever quite as simple as it could be, is it? ;)

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Just to clarify.... the engine was running immediately prior to the underfloor pump and filter being replaced? Is the fault "rail pressure monitoring" still present? . The DDE needs to see a minimum rail pressure set point before it will switch on the injectors and the engine then fire up. If both the in tank and underfloor pumps are running while the engine is cranking then it may be possible that the high pressure pump still has some air bubbles inside and not reaching the DDE set point pressure. How long have you cranked the engine for in one continuous cycle?

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17 minutes ago, Lubed said:

Just to clarify.... the engine was running immediately prior to the underfloor pump and filter being replaced? Is the fault "rail pressure monitoring" still present? . The DDE needs to see a minimum rail pressure set point before it will switch on the injectors and the engine then fire up. If both the in tank and underfloor pumps are running while the engine is cranking then it may be possible that the high pressure pump still has some air bubbles inside and not reaching the DDE set point pressure. How long have you cranked the engine for in one continuous cycle?

Engine was running, and cut out while travelling at around 95km/h. Dry day, cruising, absolutely no warning.

Once recovered to home, DDE reported code 4B90. Consulting with BMW revealed this is reported when mi fuel pump fails - the in-tank pump and HP pump have discreet error codes; the mid fuel pump does not.

Replaced mid fuel pump. DDE no longer reports any errors of any sort whatsoever.

Today I paralleled a second battery and cranked the engine for 30-40 seconds (may have been longer - I wasn't timing it). Cranking speed seems fine, and at one point it almost seemed ready to fire, but no.

Air bubbles are, I think, the most likely cause but I've don't know how to bleed the HP pump.

(Apparently BMW have all sorts of problems with this, too...)

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Have you confirmed both the in tank and underfloor pumps are running while cranking and supplying pressure to the HP pump?. A good quality tester will have a fuel bleed service function to bleed the system, otherwise and couple of 30sec cranks should do the trick to bleed it if that is in fact the problem. Give your starter a chance to cool between cranking cycles.

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12 hours ago, Lubed said:

Have you confirmed both the in tank and underfloor pumps are running while cranking and supplying pressure to the HP pump?. A good quality tester will have a fuel bleed service function to bleed the system, otherwise and couple of 30sec cranks should do the trick to bleed it if that is in fact the problem. Give your starter a chance to cool between cranking cycles.

The Scanner is a purely diagnostic tool - it reads codes and reports them, but doesn't interact in the way INPA does. That's where I need a new cable in order to 'talk' to the car. It's planned, but small expenditures have to be planned at the moment!

I'll try extended cranking again and see if that gets me anywhere.

Thanks.

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21 minutes ago, gjm said:

The Scanner is a purely diagnostic tool - it reads codes and reports them, but doesn't interact in the way INPA does.

That only applies to cheaper versions of "scanners" 

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15 minutes ago, *Glenn* said:

That only applies to cheaper versions of "scanners" 

Absolutely. I unreservedly acknowledge the tool I'm using isn't especially advanced! But it's better than nothing.

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I know. But it's not going to help you resolve the problem with the info it has given you previously and what you are now getting after doing the initial repair.

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Got all the factory software working on a laptop you could borrow but I may be a bit far away for you.

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3 hours ago, *Glenn* said:

I know. But it's not going to help you resolve the problem with the info it has given you previously and what you are now getting after doing the initial repair.

Agreed. Definitely a case of no longer the right tool for the job.
I've also found that shouting at the laptop and car and asking "if there's no #$%^** problem, why won't you $%^*^&* start?" doesn't actually work. 😬 ;)

2 hours ago, Eagle said:

Got all the factory software working on a laptop you could borrow but I may be a bit far away for you.

Hamilton? That's (almost) next door!
We'll be in town on Saturday - Miss M's 18th birthday party. I have INPA installed but don't have an appropriate cable. Certainly be keen on borrowing something that might just help. 👍 🙏
(Didn't realise you also have an S600... 💖 )

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