Help! Tranny swap gone wrong?

So my tranny went out on my 95 525i. Pulled a tranny from another 95 525i. Swap went well and only issue was now it wont start. Starter works fine. Has good fuel pressure. Has compression. Has air. Just no start. Checked all my work over. Everything is good. Ran fine before swap. Got curious and tan the vin on the bellhousing on the tranny I got and found out it came from a 93 525i and nor a 95. So would the tranny computer for a 95 work with a 93 or would that be the whole problem with my no start?

If the plugs all line up I would think it would work. I'm sure It's in a anti theft mode or something.

Is there a way to by pass the anti theft to test that? I dont have the key flob to set the alarm. But wouldnt the anti theft prevent the starter from cranking?

Exactly. Atleast from what I understand. I wish someone else would jump in on this, but I think there is a blue fuse under the rear seat by the battery, if you pull it I think it disarm the car.

Tward has done his tranny swap not to long ago , I'm sure he would know .

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Pulled the fuse and it still didnt start. Decided to clean the connecters for the tcm and it fired up after a few trys. Let it run for a few mins to get the tranny fluid topped off. turned it off the restarted it. Fired up fine. Drove around the block a few times shifted a bit rough. Got home and it started idling really rough and died. Hasnt been able to restart since. So were back to square one.

Fuel, air, spark, and compression...

Are you dealing with an auto or manual?

Has fuel, air, spark, and compression. its an automatic transmission.

Originally Posted by Shaske87

Has fuel, air, spark, and compression. its an automatic transmission.

Have you done the stomp test? If not, do it to see if there is an error code stored in the computer.

Did the stomp test. No codes being stored.

Just noticed that when I go through the gears to neutral the N in the dash doesent appear. All other letters and numbers work. Is this a possible sign of anything?

Originally Posted by Shaske87

Has fuel, air, spark, and compression. its an automatic transmission.

My bad T , it was not specified in op first post . Tranny swap I assumed it was like what u did to your e34 swap an auto to a stick .

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Well It's electrical. It's Wierd that it seems to be the TCM causing it. Can you swap TCMs? Take the old one and put it on the new one?

I'm assuming it cranks fine? Not that It's a weak battery causing this.