Help identifying plug near bell housing (E24)

03F · 01-23-2026, 09:02 PM

Cousin sent down his 15 yr+ project for me to have. He sent it after it was engine and manual swapped. Car has not started since the swap. I got battery wiring done, electronics turn on, starter clicks, but engine doesn't crank.

Does this plug near the bell housing have something to do with that? I just noticed it today.

Hopefully you can see in the photos…
(taken from drivers side of engine bay)

John in VA · 01-25-2026, 08:50 AM

I wish I knew, but try asking at the E28 or Big Coupe forums. Good luck!

https://bigcoupe.com/phpBB3/index.php

https://forums.mye28.com/index.php

M-technik-3 · 01-25-2026, 09:31 AM

Those are reference sensors. Motronic 1.0 had them on variety of chassis.

03F · 01-26-2026, 02:48 PM

Quote:

Originally Posted by M-technik-3

Those are reference sensors. Motronic 1.0 had them on variety of chassis.

Sorry, should have put more info.

The car is an ‘89. iirc, isn’t it Motronic 1.3?

Engines out of a 90 535i

John in VA · 01-26-2026, 03:57 PM

Quote:

Originally Posted by 03F

Engines out of a 90 535i

You need to talk to the E34 or E38 folks.

M-technik-3 · 01-26-2026, 04:58 PM

So car is running fine without it? I would set up an account on https://bigcoupe.com/phpBB3/index.php

03F · 01-30-2026, 12:32 PM

Quote:

Originally Posted by M-technik-3

So car is running fine without it? I would set up an account on https://bigcoupe.com/phpBB3/index.php

Unfortunately no, I have never seen the car run. Was seeing if this could be one of the many reasons why.

Think I’m going to have to make an account, was trying to avoid the $75 registration.

M-technik-3 · 01-30-2026, 05:19 PM

Go to mye28.com and present the question they have the same drivetrain.

01-23-2026, 09:02 PM	#1
03F Registered 6 Rep 3 Posts Drives: 335i, 635CSi Join Date: Jan 2026 Location: Los Angeles iTrader: (0)	Help identifying plug near bell housing (E24) Cousin sent down his 15 yr+ project for me to have. He sent it after it was engine and manual swapped. Car has not started since the swap. I got battery wiring done, electronics turn on, starter clicks, but engine doesn't crank. Does this plug near the bell housing have something to do with that? I just noticed it today. Hopefully you can see in the photos… (taken from drivers side of engine bay) Attached Images Last edited by 03F; 01-23-2026 at 09:03 PM..
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01-25-2026, 08:50 AM	#2
John in VA Colonel 1870 Rep 2,730 Posts Drives: 2015 228i M Sport Join Date: Jul 2007 Location: Leesburg, VA iTrader: (6)	I wish I knew, but try asking at the E28 or Big Coupe forums. Good luck! https://bigcoupe.com/phpBB3/index.php https://forums.mye28.com/index.php __________________ ____________________________________________ 2015 BMW 228i in EstorilBlau II Metallic / Terra Dakota Leather - 6-speed manual, M Sport Package, Cold Weather Package, Lighting Package, Premium Package, Harman Kardon premium sound, Anti-theft alarm system, Blue Metallic Matt Accent Moldings, Aluminum Hexagon Interior Strips, Anthracite Headlining
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01-25-2026, 09:31 AM	#3
M-technik-3 Colonel 3817 Rep 2,117 Posts Drives: E30 M3, E36 M3, 328iT, 335i Join Date: Mar 2020 Location: western Ma iTrader: (0) Garage List 1995 M3 [9.33] 2007 E91 [8.17] 1988 M3 [9.60]	Those are reference sensors. Motronic 1.0 had them on variety of chassis.
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01-26-2026, 04:58 PM	#6
M-technik-3 Colonel 3817 Rep 2,117 Posts Drives: E30 M3, E36 M3, 328iT, 335i Join Date: Mar 2020 Location: western Ma iTrader: (0) Garage List 1995 M3 [9.33] 2007 E91 [8.17] 1988 M3 [9.60]	So car is running fine without it? I would set up an account on https://bigcoupe.com/phpBB3/index.php
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01-30-2026, 05:19 PM	#8
M-technik-3 Colonel 3817 Rep 2,117 Posts Drives: E30 M3, E36 M3, 328iT, 335i Join Date: Mar 2020 Location: western Ma iTrader: (0) Garage List 1995 M3 [9.33] 2007 E91 [8.17] 1988 M3 [9.60]	Go to mye28.com and present the question they have the same drivetrain.
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