Help Me Sort This M30B35 Engine Harness

ClayW

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I need help Identifying which plug does what on this engine harness for an M30B35. Unfortunately, I didn't pull it, so nothing is labelled.

Here's what I've got so far:
1 - Tank vent
5 - O2 Sensor
8 - DME
10 - 12V Battery Power
17 - TPS
22 - AFM


11 & 12 are obviously relays, but I'm not sure which one is which, so I don't know which relays to get.

Thanks in advance.

M30B35Harness.jpg
 

HB Chris

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The color of the wire and type of connector plug will help determine where they go. The relays on a b35 are for the ecu and the fuel pump. There are basically seven wires that connect to the chassis harness which you can splice in next to the brake booster. On my harness I removed the diagnostic plug and it’s wires. I can provide some pics if needed.

Chris
 

BuzzBomb

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1 - Purge valve - It's use depends on what intake manifold you intend to use. If you are want to use the original L-Jet logs, just cut it off.
2,3 - Starter Solenoid - You only need the black w/ yellow striped wire which is your starter trigger.
4 - Connector to the ALT sub harness. If you don't have that harness, you'll need to run a +12 to the ALT from the starter +12 pole, and pick up the blue (CHG light) wire to connect to the engine bay harness (cluster)
5 - O2 Sensor
6 - Oil Pressure (You'll need a oil pressure sender with a Bosch connection)
7 - Idle Control Valve
8 - DME (179)
9 - DME compartment fan (not used)
10 - 12V Battery Power
11 - Fuel Pump Relay (Orange)
12 - Main Relay (white)
13,14 - Grounds for DME
15 - Coil +
16 - Coil -
17 - TPS (You only need three of the wires in that connection if you want to replace the Auto TPS with an original style one)
18 - Thermo-Time Switch (Blue plastic sender in the thermostat housing)
19 - Temp Sender (You'll only use one of the wires and connect it to your original spade connector temp sender)
20 - Crank Position Sensor (Motronic 1.3)
21 - #6 Spark Plug Wire Pickup (Motronic 1.3 )
22 - AFM (Motronic 1.0-1.3)
 
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ClayW

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1 - Purge valve - It's use depends on what intake manifold you intend to use. If you are want to use the original L-Jet logs, just cut it off.
2,3 - Starter Solenoid - You only need the black w/ yellow striped wire which is your starter trigger.
4 - Connector to the ALT sub harness. If you don't have that harness, you'll need to run a +12 to the ALT from the starter +12 pole, and pick up the blue (CHG light) wire to connect to the engine bay harness (cluster)
5 - O2 Sensor
6 - Oil Pressure (You'll need a oil pressure sender with a Bosch connection)
7 - Idle Control Valve
8 - DME (179)
9 - DME compartment fan (not used)
10 - 12V Battery Power
11 - Fuel Pump Relay (Orange)
12 - Main Relay (white)
13,14 - Grounds for DME
15 - Coil +
16 - Coil -
17 - TPS (You only need three of the wires in that connection if you want to replace the Auto TPS with an original style one)
18 - Thermo-Time Switch (Blue plastic sender in the thermostat housing)
19 - Temp Sender (You'll only use one of the wires and connect it to your original spade connector temp sender)
20 - Crank Position Sensor (Motronic 1.3)
21 - #6 Spark Plug Wire Pickup (Motronic 1.3 )
22 - AFM (Motronic 1.0-1.3)
Thank you!
 

BuzzBomb

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Also, there are a lot of redundant wires in that B35 harness, especially the Auto fitted harness. If you want an more period look, you can pare it down to half it's size by using only what you actually need and re-wrap it.
 

BuzzBomb

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In an E9, since there is no check engine light or service interval, the only thing it could be used for is a remote starter trigger but it’s so unlikely that you would ever use it that it’s better to just remove it in most cases.
 
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