P38A A series of faults

Evening all, a confession; it has been many years since I last posted and that was way back in 2006 when I picked up Letti my hybrid 88" IIA. She's still in kit form, has had various engines bought and sold for her and has been joined by a pair of early Series III 109"s one still complete the other in kit form.

Anyhoo, I'm in the midst of a messy divorce and using man maths reasoned that it would be cheaper to buy a suitable tow vehicle rather than hire one to slowly move my many projects to a new home (there's more besides the Land Rovers...) so in a rash ebay moment I bought a leggy (215k miles) late 95 'N' reg P38A DSE that's sitting on its bumpstops for what I thought was, relatively speaking, buttons. Initially, I was going to simply throw an air-to-coil kit at it and get on with giving it a thorough service before sending it off for a fresh ticket and start making use of it to drag back a project at a time while collecting my son for the weekend.

But while waiting for it to be delivered I started reading up on the EAS system on here and elsewhere and my thought patterns changed (mostly because I do prefer to 'fix' things rather than throw parts at them, but also because I am tight as well as brassic from the never-ending solicitors fees). I have downloaded a copy of EASunlock, have a cable inbound from P38spares and some push-fit 'emergency' valves coming to at least allow me to see if the airbags are intact. I've also downloaded a workshop manual, a few how-to guides (inc from here) and have been trying to piece things together.

Meanwhile this morning my latest questionable choice arrived and was driven off the back off the delivery wagon.

First thing I noted was that it was a little reluctant to start, just taking a little longer spin over, but once running sounded nigh on identical to an M57 engined 530d I ran for 8 years, ie pretty damn smooth for a diesel.

I then had a quick poke around the engine bay chatting to the chap (trader) who I'd bought it from and noticed that despite the very tired paint and a leaking cam cover (no surprise the gasket goes hard and did on my 530d, but at least on the M51 it's a simple rocker cover) as well as a rather loose cam cover breather connection, that someone had been spending some money under the bonnet to the tune of: a brand new ABS pump and accumulator, what looked like brand new EAS pump and possibly a new distribution block and actuators (or at least it had been out and rebuilt). Hum, money has been spent on expensive parts and it still doesn't work...okaaay

Getting into the drivers seat, key in the ignition and switch to position 1, EAS Christmas tree, ABS pump prime and turn off but ABS light still on, many bongs, and hard to read warnings on a half faintly glowing lcd display muttering something about windows not being set or something and some thoughts sprang to mind...mostly concerning the BeCM...reluctant start, complaints about electric windows, ABS uncertainty and an EAS system that appears dead starts a rising panic that I've got a bit more of a problem on my hands than a few O rings...

Battery is on charge incidentally and I'll check how it is tomorrow, just in case it is that simple (unlikely)

So I'm throwing it out there to the knowledge pool, any thoughts?

And while I at it; M51 timing chains (more specifically the guides and tensioners) do they give problems, and can the ZF auto box undergo an oil change without resulting in a world of pain (unlike the bloody GM box used in the 530d mutter mutter...)?

Windows not set happens every time you disconnect the battery. Easy to reset them, just hold the switch on each for a full cycle open to closed again.

And auto box fluid change is easy to do.

Oh, if you haven't already, download a copy of RAVE.

The BECM is basically nothing to do with the issues you have, with the exception of the windows. The windows require re-setting if you disconnect the battery. Simply hold the button to lower the window all the way, then hold it to wind it up all the way, pausing, finger on the button for a second or so once fully up. that should be job done and the dash should say (for example) RF Window Set. If it doesn’t set first go, do it again. It is all about the car knowing when the window is home and working out the motor stall current so it can cut the power if something is trapped in the window.

Whilst not a diesel owner, I understand that reluctance to start could be (on a high mileage engine) a stretched timing chain, setting the timing off. I have heard of people slackening off the pump and giving it a very small nudge, in the right direction, to make up for the slack in the chain.

ABS light will remain on until you do over 5 MPH as the system needs to check all is well and it is getting signal from all the sensors etc.

There shouldn’t be an issue in doing an oil change on the ZF. Best advice, park the vehicle up the night before you want to do the change, in the spot where you are going to do the work, so you don’t have to start the vehicle next day. This ensures you get the maximum fluid out in one go. Drain off the fluid (you should get about 6 litres) then remove the pan and filter and replace the filter and pan gasket. Getting the fluid back into the transmission will depend on the model you have, but is either through the dip stick tube, or a fill plug on the transmission. In either case fill to the mark (or until it weeps from the plug hole. Start the car, cycle the gears, and with the engine running fill to the mark or until it weeps from the hole again. Obviously, assuming the fluid was up the the make, you will put ion about the same amount you drained off.

As for the EAS, black magic for me, mine is, very thankfully, on standard height coils, and in the years I have owned it, I have never come out to find it sitting on the bump stops . Seriously though, you might need a Nanocom or similar to do some system re-setting.

RAVE would be the workshop manual right? If so I've done so already
The window thing is curious as I did cycle them all when I first got in it to see if that might make a difference, and to see if they worked, and that didn't seem to reset the error message. Battery has been disconnected while it was on charge, so I'll try it again once I reconnect it.
My 530d GM autobox oil change experience resulted in terminal failure due to it having gone past the point of no return on wear by the time I changed the oil (over 100k miles) as it was deemed 'sealed for life' by BMW, and in need of an oil change every 60k miles by GM

Try changing the glow plugs and leak off pipes at the same time, they prefer the proper Bosch plugs. Check the clear hose that goes between the fuel filter and pump, if there’s air bubbles it’s got a leak somewhere. Usually the intake pump.

as for the auto box, treat it to a new filter and a couple of changes to get all the old stuff out. Worth giving the engine a good service whilst you’re at it too, you’ll notice such a difference.

If this link works, here is a copy of the workshop manual.

Top tips, thanks all.
Sounds like the M51 potentially does suffer the guide/tensioner wear of other similar generation BMW engines, will get my borescope in there for a look-see

Yup, that's the manual I found and downloaded earlier, bit of a long read at 1361 pages...
Breathing a sigh of relief that the BeCM may not be the source of my problems, as while the carpet on the drivers side is damp, it does seem dry under the seat having popped the trim off for access to the brain

Slooby said:

Yup, that's the manual I found and downloaded earlier, bit of a long read at 1361 pages...
Breathing a sigh of relief that the BeCM may not be the source of my problems, as while the carpet on the drivers side is damp, it does seem dry under the seat having popped the trim off for access to the brain

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Wet carpet could mean heater matrix o rings.

Could be, but noted new genuine part heater hoses had been fitted relatively recently. I'll take some pics in daylight

P38-DFX said:

Try changing the glow plugs and leak off pipes at the same time, they prefer the proper Bosch plugs. Check the clear hose that goes between the fuel filter and pump, if there’s air bubbles it’s got a leak somewhere. Usually the intake pump.

as for the auto box, treat it to a new filter and a couple of changes to get all the old stuff out. Worth giving the engine a good service whilst you’re at it too, you’ll notice such a difference.

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+1 on glows but Beru are the brand of choice and I think what went in originally.

The M51 does suffer from chain atretch but usually it results in difficulty starting hot rather than cold. Leak off pipes may well have perished (need proper Bosch stuff as the cheap stuff won't last 6 months) and lift pumps can fail but otger than that it is a pretty bullet-proof engine.

The LCD display Illumination bulbs can be had off the Bay for under a fiver delivered.

Biggest danger now is burning out the new EAS compressor before you find the leak.

Slooby said:

Top tips, thanks all.
Sounds like the M51 potentially does suffer the guide/tensioner wear of other similar generation BMW engines, will get my borescope in there for a look-see

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Modulation can be checked with Nanocom. Static timing is with a dial-guage as per RAVE. First sign of trouble on the auto is usually the injector light flashing on the dash as you lift off the throttle approaching roundabouts.

Does the M51 run an electric lift pump in the tank and a second electric supply pump in line on a chassis rail before reaching the mechanical injector pump then? The supply pump was a notorious issue on cars fitted with the M57 so been there done that with starting and running problems!

As for the EAS pump I'm hoping I can test for leaks without relying on it too much by using the push fit valves

Slooby said:

Does the M51 run an electric lift pump in the tank and a second electric supply pump in line on a chassis rail before reaching the mechanical injector pump then? The supply pump was a notorious issue on cars fitted with the M57 so been there done that with starting and running problems!

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Only an intank pump on the 38.

Ta, will take a look at how it's behaving then

Slooby said:

Ta, will take a look at how it's behaving then

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If you look in the Technical Archive there's a how to check.

Glad you're keeping the EAS by the way.

As long as the cost of the parts to fix it stay no greater than to go coils...ish...