E30 swap No crank No start

[Jam53]

Got a 89” auto 325i with a blown motor awhile ago and picked up a 94” manual 325is motor with red 413 DME to put in it. While after a few nights and a lot of curse words and slurs I get it in there. I go to start it and nothing: just a click of the starter. Also I have found that I get no fuel or spark.

things I’ve done:

Checked battery. It had 11.6v so I stuck a jump pack on it to give it some juice still just a click.
Checked crank sensor. Got 519 ohms not to sure if that’s good so I’m going to replace it just in case.
I tried to hit the starter in case it was stuck and needed to be freed. Nothing
I turned the engine manually to make sure it is free.
I will be putting jumper cables on it to check ground later.
At this point any help or ideas would be great. Trying to get it on the road before the Minnesota winter.

[shogun]

Get a new battery. A charged battery has 12.6 to 12.7 volts. 11.6 volts is a dead battery. https://www.batteriesplus.com/blog/p...of-car-battery

[Jam53]

Not it I put a new battery from another car on it and same thing.

[328 Power 04]

Can you be sure that the starter is good?

A bad or even missing crank sensor will not stop the engine from spinning around. So if it's not a voltage issue, then I'd question that starter a bit.

[323i E30]

Double check if the nut holding the wiring to the starter is tight.
It’s silly, but I’ve had my starter click without cranking because of that.

[Jam53]

Ok 328 Power 04 both you and 323i E30 are right I'm not 100% sure the starter is good or the bolt is tight so I'll check this evening and update on the result.

[Jam53]

Yea so the starter wire was the issue it wasn’t tight but now I’m stuck with a crank no start, I even added starting fluid. I will be checking to see if the fuel pump kicks in and go from there.

[323i E30]

Nice. Simply solved issues are the best.

Do you see any movement in the needle of the tach while cranking? If yes, then your crank sensor is probably fine (I have no knowledge of the ohms it should read).
To be honest, I would get the engine management computer read out, and go from there. Not just the codes, but also the descriptions.

[bmwdirtracer]

No good wondering about fuel, if the DME isn't trying to start the car.

There is certainly much to be considered here: You're swapping an M50 into a car that had an M20, correct? Have you compared all the wiring diagrams for both the donor and the recipient cars? It's almost certain that the two DME's and wiring harnesses do not share the same inputs and outputs.

If you HAVE done all the homework involved in such a swap, poring over dozens of pages of wiring diagrams, please let us know. If not, you have a metric ton of work ahead of you.

[Jam53]

I can say I have done enough research that I’ll probably won’t be doing any swaps for awhile after this. That being said you are correct it is a M50 going into the M20. I was able to make the C101 harness and am very confident that it’s good. I have read about a C104 harness just wondering if the 89 models have it as well could not find the answer online. Moreover I can’t pull code are any cuz the car is OBD1 and I don’t have the connector.

[bmwdirtracer]

http://wedophones.com/BMWManualsLead.htm

It appears that an '89 does have a C104. I haven't tried to research what it does, since it's only two pins. However, the '94 is the engine you're looking to start, so that's where I'd start your exploration of wiring diagrams, and what the DME is looking for to start the car. My home computer seems to be working rather slowly tonight, so I can't adequately cross-reference diagrams, but I think you need to have a look at the X20 connector; where the body and the engine harnesses connect on an E36.

Please note that this is entirely from memory, I can't seem to pull up the diagrams I've just linked you to, above.

EDIT: Okay, I've pulled up those diagrams now, and yes, pretty much everything goes through the X20 on an E36, and a couple of crucial connections go through the C104 on an E30.

When I last did an engine swap, much simpler than yours, I spent MANY hours poring through and comparing , side by side, the diagrams of the two cars involved.

[Jam53]

Ok looks like once again I have to look at more diagrams and thanks for the heads up about the C104. I will be seeing what wires need to be connect to the DME so it gets the signal it needs to start.

[bmwdirtracer]

have you visited the Engine Swap forum, at these Bimmerforums? Your swap should be very well covered there; it's quite possible there's even a swap wiring harness for it somewhere, for sale?

[Jam53]

I am officially perplexed because I still can’t get this thing started so far has checked all grounds and powers checked most of the wires and all of it comes up good. Also I did post it on there but the response are alot better here.

[bmwdirtracer]

How did you come by this engine? Was the engine wiring harness intact and undisturbed, with all sensors plugged in? How about the DME relay? Are you using the E30's, and if so, have you connected it properly to the M50's DME?

Do you have power at the injectors with the ignition on? How about the coils?

Pin 21 of the M50's X20 connector would carry the ignition switch's power to the coils on a 2.5mm green wire. Is that wire hot with ignition on?