It probably has an emulator fitted, rather than being 'programmed out'
Works well enough if done right - my M57 ECU is the same. Someone has recently done one for the Thor ECU too.
The emulator just sends the code the BeCM would have sent, as you'd expect.
Yes, you need to go into Motronic and look at what the immobilisation code is. Take a note of it.
Then go into BECM and either 'other' or 'alarm' and find where it should be - it will likely be different. You can change it here though, enter the code you noted from Motronic. Then write the settings, disconnect, and it should start up.
Well, the sump won't fit, nor will the turbo actuator - so you'll need to fabricate some things to deal with both.
The BECM just needs to see an engine speed to know the engine is running - that signal is then used to wake various things up. Conveniently, the M57 ECU outputs the same 3 pulses per revolution on an analogue output as the M51 diesel would have done. This does mean the instrument cluster needs swapping to a diesel version, or the tachometer would not read correctly. This is because the V8 outputs 4 pulses per revolution.
The gearbox ECU has been replaced with a compushift - which long term, I will be keeping, as it offers complete control over the shifting of the box. I still need to tweak this some more to get it 'just right' for me, but its only a couple of odd situations where it shifts a bit harshly for my liking currently.
It certainly isn't a drop in replacement - nothing about this really has been. The power steering maybe? Only needed one pipe bending to fit :)
There won't have really been a difference - but who knows in the 20+ years of the cars life if it has had the terminal cut off and a new one fitted, or if the battery leads available on that day of production were just slightly shorter...
Many many people have fitted MF31 type batteries without issue :)
The Grom is certainly the easiest way to go if you have a working DSP system or even the Alpine with door amps. I had one to start with and was perfectly happy with it - I just went another route later on.
I have a nice unopened jug of what I'm going to start calling 'summer currency' at home ready for filling up once I've pressure tested it etc.
Yeah its a similar capacity compressor thankfully, so it should be up to the job. BMW used the same one on the E39 as they did on the E53 X5, and its very similar to the L322 one.
But the E39/early E53 have a huge 28mm suction port for some reason. Could go the late E53 or L322 one, but the port is in a different spot that is more of a pain to work with - and I have the E39 one already. Either way, the actual suction lines are the same so I have enough bits to marry up with some Eaton pushfit hose bits to join it all up. Once the fitting has been made :) Hopefully next weekend's job.
Good to know it helps there :) I think its mainly preventing corruption, as it will only pass through what appears to be valid data for the P38. But its a bit of a dark art honestly in how it works. Early 90s communications... I'm just glad we're done on the development work with it these days as it was fairly headache inducing!
Makes canbus look trivial... fun fact: my own P38 has at this point three additional microprocessor based control units. One for my diesel heater control/timer, one for the inverter control, and one that reads canbus from my engine ECU to drive the P38 temp gauge, my cooling fan, and AC clutch go/nogo. All three individually have more processing power than the BeCM has... just goes to show though - they did a lot with very little power back in the day. But its all voodoo and magic if you try and figure it out 25 years later.
AC... one custom suction port fitting prototyped and ready to be machined from aluminium shortly:
I will be using the V8 pipework setup, with custom soft lines between the compressor and rest of suction line (the big one) and the condenser. They will come out the front of the engine between the engine itself and radiator/cooling fan.
I've seen some have used the P38 diesel setup, but usually they have removed the airbox from the engine to give space. I'm not doing that, and I don't like the way they would sit. Hence going the long way around. I think the charge will be about the same as the Thor V8 anyway as it all works out to be pretty much the same length.
The steering box bolt will be swapped around so the head is on the inside, just to give it a bit more clearance for my peace of mind - but there is more room than appears in the picture.
I'd run the output of the CTek to at least one of the three BeCM terminals under the seat if you want to connect it inside the car. If its an MXS5.0 then a 4mm cable from under the seat to the loadspace would be fine, fused down at the terminal to 10 amps. Yes 4mm is overkill for 5 amps, but you want a decent connection to minimise voltage drop between the charger's sense circuitry and the battery you're charging.
Otherwise (for example, using the tow bar perm 12v) you have a myriad of wiring and other connections that will add to the resistance and potentially confuse the charger. The wiring is all old now as are the connections. Those three BeCM feeds are 6mm^2 back to the fusebox, via a maxi fuse each and then onto the battery. About the best you'll find inside the car for charging.
A direct connection back to the battery (suitably fused at battery end of course) would be best. Or just fit one of the CTek weatherproof sockets onto the battery terminals and place it somewhere convenient?
I am aware - we designed the filter from the ground up, we have prototyped an entirely new receiver with filtering built in as part of its output, but decided it wasn't worth the hassle, because the way the system works it wouldn't help improve key responsiveness. Not because of the receiver, but the key itself.
Other marques of the time faired far better in terms of being able to still receive a transmission properly from a key even in areas of strong (or even intentional) interference. The P38 setup just has very poor error handling - it basically doesn't. So unless it gets a perfect transmission start to finish, it drops it.
We have future plans for a new fix for this, and have already prototyped a solution. Whether it will make it to production or not is another matter. The filter solves the main problems, and is well proven at this point.
Speaking of... another 60 to build in the coming weeks.
The thing is the filter can't deal with the receiver being desensitised, as it's dealing with the output of the receiver. The LR offering is the same, it's just the nature of the whole design unfortunately.
The main thing beyond stopping battery drain is preventing memory corruption of the becm by interference, which is what screws things up properly and can cause things to go into lockout meltdowns etc.
I'll elaborate - I'm not saying the filter will be able to receive a proper signal if it is being overwhelmed by other noise, but it will stop anything that isn't a P38 key from getting to the BECM. Including potentially this CDMA phone noise. Bearing in mind the original receivers would send out pretty much anything that came in be it on 433/315 or harmonics thereof.
At some point we'll put one on the scope and show the crap that comes out.
Amusingly enough, I was looking at electrical engine issues on a P38 yesterday that I have a suspicion might have had one of our filters fitted to it by its previous owner - when I go back with some bits to look at the engine loom issues, I'll have a peek and see if it does. They've gotten quite far and wide these days and I'm happy we've been able to help solve the old battery drain RF issue. As said - without the green oval tax.
Sounds like another issue our filters would solve :) when more components turn up to build a new batch at least...
Would need to do some more testing but from a technical standpoint, that doesn't make much sense as the RF receiver does just that - receive. Even the friendly syncing functionality of later P38s is only initiated by the inductive coil around the ignition barrel - its very short range and only activates when told do with a key in the barrel etc.
Other than that, there isn't any kind of two way comms between the remote fob and the car. Strange indeed.
Thanks gents :)
The air filter is actually hiding inside the airbox that makes up part of the engine's top covers - its the hole front to back side behind the oil filler. The air intake to that you can see to the side of the engine - one day I might duct that to somewhere cooler but for now its working well enough.
Little update:
Engine covers all now on, red pipes replaced for more black. Bracket for the EAS drier canister.
Next up is AC pipework. Need a custom suction port fitting for my compressor machining - once I've got that, it will all go back together and I'll fill it up.
Hmm. To crank = to spin the engine over, but not necessarily actually fire up and run.
Has it not actually been spinning over at all as part of the original problem? If so.. yeah, sounds like the starters gone.