m20b25 in 91 318is. Wiring Help

[Fcknslo]

Picked up a car with the swap and it cranks and starts for about a second then shuts off. I'm not exactly sure what car the engine came from but I'm trying to get the wiring correct because I have a feeling thats my problem.
He has one big green wire that is off the dme thats a thick green wire thats going to the c101 plug but It came loose and I'm not sure what port to put it in. and the green if i'm not mistaken from the c104 plug going to under the steering wheel connected to two other green wires.

Does this make any sense? I'll post pics up in a second but other than that I'm at a total stand still. I'm not sure where to go from here.
any help or assitance would greatly be appreciated

[jlevie]

You are going to need to consult the wiring diagrams (see http://wedophones.com/BMWManualsLead.htm) to get this right. From memory the large green wires off the connector on the steering column are hot in run or start.

If the engine cranks and runs for a few seconds I tend to discount the wiring as being the cause. That sounds more like a fuel delivery problem. Tee in a gage to the fuel rail and see what the fuel pressure is doing when you try to start the engine.

[Fcknslo]

even if so posting pics in a second. I would like to see what exactly the wires are connected to and why they are connected the way he did it.
I'll post pics in 2 min.

[Fcknslo]

those are splices under glove box near dme

Splices under driver side steering wheel

c101 plug green thick wire connected to black wire but the black wire fell out, not sure what port its suposed to be in.

[Fcknslo]

another question is. is there any way to test the dme to ensure its properly working?

[Fcknslo]

bump...

[Fcknslo]

bump. please i need this fixed.

[Fcknslo]

bump.

[FredK]

The wire from the C104 going underneath the dash is probably going to a switched hot (hot in start and run). This is a required connection.

I have no idea what that thick green wire coming off the harness is. Hopefully someone else does!

Does your tach even work?

[Fcknslo]

tach does not work. I'm still stumped and its been over two weeks. I'm scared to even bring it to a shop because they might not even know.
thanks fred for all your help.

[Fcknslo]

that thick green wire goes to 101 plug so assuming its important.
it got loose and came out of where it originally was and maybe thats why my car starts but dies immediatly after. i'm not sure what to think anymore i'm beyond stumped.

[FredK]

You know what would help, is if you undid the C101 (unclip it, twist 90 degrees counterclockwise) and look at the face of the connector really carefully.

Each pin is numbered, from 1-20. Are there any pins that are missing a wire (look at the back of it)?

The tach signal comes from the C104, from the black wire.

[Fcknslo]

there are multiple pins out of the 101 plug that are missing. and i'm not quite sure what they are. I'm sure they might have relevance as to why my car is not starting. for b25's is there certain pins that need to be plugged in for it to start or do all of them need a connection because i have like 7 pins open right now. I'll go out in a bit and check which ones are open.

[FredK]

Hm, well you only NEED like 4 pins to get the car started and running.

There should be a lot of unoccupied holes in the C101. You should have eight open holes. There's that red wire stuffed in the C101 for really no reason, if it's a ground.

Let me know if that red wire is in Pin 20.

[whatt18yahoo]

i gotta tell you dude ecu wiring is not exactly my thing. check this out

http://www.armchair.mb.ca/~dave/BMW/e30/

he knows his shit but you have to look for what you need. i used this resource to sort out my chassis electrical issues on the e34 and it worked incredibly well. i will warn you to be detail oriented here. good luck. sorry i can't be more help, i'll talk to travis and see if he can help you more than i.