1988 635csi 5-speed swap.

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kylefav390
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1988 635csi 5-speed swap.

Post by kylefav390 »

So as the title states I am in the process of doing an overall engine refresh and a swap to a manual trans. I'm nearing the point of doing all the electrical components of the swap, and that's where i'm running into questions. So as I understand some people completely remove the auto wiring harness from the car, which is something i'm willing to do if necessary. However I'd rather leave the existing harness in place and ground the neutral safety switch, so the car will start. I've found a few threads, but most are for earlier model cars and the one thread for a late model 6er they completely removed the harness. So with leaving the wiring in place, what else do I need to do so the car will start and run properly? Thanks in advance!
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86_6series
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Re: 1988 635csi 5-speed swap.

Post by 86_6series »

We left the AT harness in place and jumped the NS switch,
connected the back up light harness.

I'll alert Jody about your post. He's a wiz on doing the swap.

Bob V
86-635CSi
96-MB C220 SOLD
98-740i
71-Continental MK3
kylefav390
Posts: 212
Joined: Wed Nov 20, 2013 4:17 pm
Location: Massachusetts, U.S.

Re: 1988 635csi 5-speed swap.

Post by kylefav390 »

I'd appreciate that! Thanks for your answer. I've also read about the TPS causing issues, or potentially needing to swap it over for one from a manual car and wiring that in properly. Just trying to nail down exactly what I need to do.
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86_6series
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Re: 1988 635csi 5-speed swap.

Post by 86_6series »

Not necessary to swap out the TPS. Auto has 5 wires the manual has 3.
Look @ pgs 1360-2 & 1360-3. Auto trans to manual. The ecu still gets throttle position from the "VL" wires.
I think that once the harness is no longer connected to the auto box the extra wires from the TPS are voided.
The TPS to the ecu is idle and wot. The pentameter is for the auto ""I THINK"""

http://wedophones.com/Manuals/BMW/1986% ... Manual.pdf
86-635CSi
96-MB C220 SOLD
98-740i
71-Continental MK3
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