MS3X on BMW E36

[LoukakIS]

I have a BMW E363.18is and I'm trying to run it with MS3X.
I am finished with the wiring but I have no spark and injection at all.
As I read I will probably need 4 BIP373 transistors, but I can't understand why the injections are not working also.
Any ideas how to work my injections and sparks?

Thanks

[jsmcortina]

Did you attach an MSQ and datalog ?

[electr_eng]

Actually as we can see from the wiring diagram of the car because the coils are 3-wire and the input we need is just 12Volts instead of 5Volts CMOS that MS3X gives maybe we don't need a BIP373 to just drive it. Can we maybe use an other small Darlington transistor that can handle this voltage?

[LoukakIS]

I attached the msq, sorry no datalog saved I will save one tomorrow

[jsmcortina]

Nothing obviously problematic with your MSQ.

How did things go when you did the coil and injector testing in the Quickstart guide?

James

[LoukakIS]

The fuel pump was ok, but sparks and injection didn't do anything...

[jsmcortina]

How are the injectors wired?

James

[electr_eng]

One pin goes to +12V when the key turns and the other pin connects directly to ms3x.

[howelll]

If the coils are the same as the m50 ones, you will need the bip drivers with a 330 ohm resistor. Optionaly you can use GM LS coils, those are logic level input.

[Matt Cramer]

If the coils are the same as the m50 ones, you will need the bip drivers with a 330 ohm resistor. Optionaly you can use GM LS coils, those are logic level input.

Yep - BMW coils are 3 wire, but they're not logic level.

Are you getting a good solid RPM signal while cranking?

[LoukakIS]

No the coils are not like M50s, they have 3wire each as Matt said(12V, groung, signal)
Here is the cable from the coils to the sparks(http://bmwfans.info/parts/catalog/E36/C ... park_plug/).
Here are my coils(http://bmwfans.info/parts/catalog/E36/C ... tion_coil/)

Yes Matt, stable rpm when cranking at 250rpm.

I attached the Darlington transistors(BC879) to convert the 5V MS3X signal to 12V. I'm going to try it in the next hours. Will that be fine?

[jsmcortina]

EDIT: See Hassmaschine's post.
That circuit won't work - the transistor will always be active.
Two options
- either swap to an NPN and invert your software output (but beware that the coils may be on briefly at powerup)
- or better use an NPN pre-driver to that circuit something like this:

NPN pre-driver to PNP

npn-pnp.png (4.68 KiB) Viewed 1318 times

James

[hassmaschine]

No the coils are not like M50s, they have 3wire each as Matt said(12V, groung, signal)
Here is the cable from the coils to the sparks(http://bmwfans.info/parts/catalog/E36/C ... park_plug/).
Here are my coils(http://bmwfans.info/parts/catalog/E36/C ... tion_coil/)

Yes Matt, stable rpm when cranking at 250rpm.

I attached the Darlington transistors(BC879) to convert the 5V MS3X signal to 12V. I'm going to try it in the next hours. Will that be fine?

actually, they are the same/similar.

the 12v is for constant power, not for the signal. you need to run BIP373s or something similar to drive them. one wire goes to switched 12v, one wire goes to MS (signal input, from BIP373s), the other goes to ground. All BMW 3 wire coils work the same way.

they are definitely not logic level coils, BMW has never used those..

[LoukakIS]

If i understand correctly the base of BIP373 goes through a resistor of 330Ohm to the spark exit of MS3X. The collector goes to +12Volt from the battery. The emmiter connects to the third pin of the coils and we live the other 2 wires of the coil (+12V,GND) as they are. If I do something else please inform me.

[howelll]

Yep - BMW coils are 3 wire, but they're not logic level.

Are you getting a good solid RPM signal while cranking?

I know they are not logic level, I use them myself. I was saying the GM coils are logic level.

[nuvolarossa]

Hi LoukakIS, I use the same coils with MS3x on my M44. They NEED BIP drivers.
I'm using a small box with 4 BIP drivers and res inside, similar to this (because I was in a hurry), but bought from extraefi.co.uk :
http://www.msextra.com/forums/viewtopic ... 67&t=36066

works perfectly with those coils. Don't know if wiring is the same with jsmcortina's one.

////////////

Pay attention because the OEM wiring in these car is mad, it drove me nuts a few days an I made confusion more than one time following BMW ETM...

At least on my M44 was like this:
There is a ECU relay that feeds +12v to stock ECU, injectors and sensors, and then there is another relay only for the ignition coils.

The coil relay is +12v under switch so that's OK, but the ECU relay (injectors..) was switched on-off from stock ECU on my M44, it supplied its relay-coil ground (86).

So I changed it's 86 ground to chassis ground and 85 wire to a +12v under key switch and all is fine without other mods.
If you grounded the ECU relay to chassis without swapping its 12v coil pin, it will stay always on, even when car parked closed without key.
////////////
Attention because people told me those coils are EASY to burn. If you can't measure dwell start with 1900us (what I'm using, I'm sure it's a little low but at least on NA I had no issues).

If you can measure dwell (with tools), please let me know how much it is!

Let me know how it goes

[LoukakIS]

Thanks Roberto for your helpful post.
I will post any result I can get.

I will buy 4 BIPs to solve it. As I see I will need also 4 resistors, 4 mica insulators and a heat sink. Do I need anything more?
I will probably try to test it today on a coil with a transistor from a destroyed MOTRONIC ECU.

I still can't get why the injections are not working. I'm giving them 12V like Roberto and groung-signal from MS3X....

[LoukakIS]

Anything I can check on the injections?

[hassmaschine]

are you getting an RPM signal? if they're getting power, and MS3 is sending them a signal, they should work without any other effort. have you verified they are getting 12v?

[jsmcortina]

Why are you running the alpha code?

Unless you can get the injectors and coils working correctly in test mode you shouldn't be trying to start the engine.

James