Fly-by wire, do I keep it?

Sat Sep 21, 2013 12:09 am

Hi
The donor for my m30 lump is e34 535i Auto and it is fly by wire throtle. It has 3 cpu's in that black box under the bonnet which I assume one is for engine managemen and one for the auto G/box, whats the other one for?

Can I keep it as fly-by-wire or is it best and easy way to somehow convert it to one that is operated with the linkage?

P.S. Is that third cpu has something to do with fly-by-wire bit and the fact that donor car has ASC button in it?

Thank you for any help provided guys

Sat Sep 21, 2013 11:07 am

This guy here was running a FBW with his M30, it can be done and maybe he could shed some light on the subject.
iirc he was losing power due to something to do with the FBW, something about a bulb springs to mind.

http://www.e30zone.net/modules.php?name ... le&u=29299

Sat Sep 21, 2013 11:24 am

FBW in use on this cabby for sale: http://www.e30zone.net/modules.php?name ... c&t=242660

Just wish I had some cash in my pocket for this!!!

Sat Sep 21, 2013 12:18 pm

Thanks I'll try asking him about this.

But would it be dificult to convert it into normal one, Is it just a simple matter of replacing the FBW body with cable operated body and it is done?
Has anyone done it here or I should have started with the cable operated one in first place?

I just been looking into them FBW things and it seems they have this habit of failing

Sun Sep 22, 2013 10:04 am

Pianist,

I got your PM, but I will answer here in case it proves useful to anyone else in the future.

The third ECU is indeed for the FBW. FBW was only fitted to E32/E34s that had the optional ASC traction control box ticked.

One thing you should know about FBW is it needs the EML (BMW's own three acronym for FBW) warning lights that came in the original E34/E32 dash. Without these lights being correctly wired in, it will always run in limp-home mode and make 105bhp. This took me two years to solve

. If you look at the pictures in my for sale ad (linked above by miniblob), you will see two extra lights above the radio. These are my EML warning lights. Simple wiring job from the correct ECU pins.

Warning lights and limp-home modes aside, I have found FBW very reliable. Mine is a little fluffy immediately off idle when the engine is cold, but I think that is more about the Fritz Bits chip than the FBW itself.

If you wanted to replace it, you would need the normal cable throttle body, the throttle cable itself, and to simply unplug the FBW ECU. I believe that the Motoronic engine ECU will happily cope with the fact that FBW has gone.

The advantages of keeping it are that the cruise control is easily transferred over from the donor, and that you keep the Sport throttle response that works in harmony with the switchable auto. You could also bring the ASC traction control across, but you would need to be clever and get the right sensors across too.

If you already have it from the donor, I would say keep it. It is no great drama to swap to cable later.

Any questions, just ask.

Martin.

Sun Sep 22, 2013 10:30 am

Here is a cheap cable (not mine)

http://www.ebay.co.uk/itm/BMW-E23-M30-T ... 3385ade9c1

And I have a m30 throttle body for sale also

Might even have a TPS and loom plug if you need it

Jim

Sun Sep 22, 2013 12:56 pm

MJJ_ZX6RR wrote:Pianist,

One thing you should know about FBW is it needs the EML (BMW's own three acronym for FBW) warning lights that came in the original E34/E32 dash. Without these lights being correctly wired in, it will always run in limp-home mode and make 105bhp. This took me two years to solve . If you look at the pictures in my for sale ad (linked above by miniblob), you will see two extra lights above the radio. These are my EML warning lights. Simple wiring job from the correct ECU pins.

So do you have the schematicks that you could share or could you tell me which pins to wire to what types of bulbs?
I will keep this as an option for now and I will try to get parts needed for cable conversion from jimbo who is proving to be very helpful in this matter.

Thing is the donor car is not with me anymore but with my stepdad (who is far far away)

I even forgot to take the blody throttle with pot box out of it and now I have to explain all on the phone to him make him remove it for me and get it posted back here

Is it easy to get the pedal out with all wiring (cable) needed?

And I like the Idea of cruise control, do I need to get the controling stick out of the donor to control it and again is it easy to remove with wires needed or can it be wired to some pins on FBW ecu using some sort of buttons?

Sorry for so many questions and
Thank you guys it is helping me a lot

P.S. Like Martin (MJJ_ZX6RR) said: it might be useful for someone in the future