E46 325 / 330i Fuel injection Wire Plug, Harness

[Liquidarthur]

This is so stupid, but I can't figure it out. There is a wire harness coming out of the back of the long plastic harness for the fuel injectors. Comes out right on top at the back. It has two wires, Brown with red and white with red. I cannot figure out for the life of me where to plug it in. Any help is appreciated.

[bmwdirtracer]

That plug goes to the engine coolant temp sensor, under the rearmost runner of the intake manifold. However, I'd like to mention that when you're looking for guidance, you need to specifically identify the vehicle. Are we dealing with a '99 M52 325, or an '05 M54 330i? It makes a lot of difference when you're trying to research a wiring diagram.......

[Liquidarthur]

That plug goes to the engine coolant temp sensor, under the rearmost runner of the intake manifold. However, I'd like to mention that when you're looking for guidance, you need to specifically identify the vehicle. Are we dealing with a '99 M52 325, or an '05 M54 330i? It makes a lot of difference when you're trying to research a wiring diagram.......

Yes and thank you for that, so it's 03 325i that Im swapping in an engine from a 530i, and I think that's what is leading to the confusion. It seems the wire on the harness from the 325 has a rectangular 2 blade plug there, however it the 3.0 engine, the only wire recepticle in the area is a roundish one with 4 pins, similar to the type that is used for O2 sensors. So I looked closely at the color codes on the wires and figured out that 2 are the same, so spliced in the round plug to the same color wires coming from the harness and plugged it in. This, of course, leaves two wires unaccounted for. Brown with a purple stripe and brown with a yellow stripe. Should I run these two currently unhooked wires over to by the computer, and splice them in to the same color? This may explain code "P1112 Engine coolant temp radiator outlet sensor high input" that im getting,

[bmwdirtracer]

No, that code is not likely to be related to what has happened at the rear of the motor. What year is the 530 harness and engine?

I have worked on many, many dozens of M54 engined cars, so I'm very familiar with their plugs. Still, there's a;ways some surprise waiting.

Let's go to the code for radiator outlet temperature: This is a plug that's in the lower radiator hose; nowhere near the back of the motor. The "dual temp sensor" at the rear of the cylinder head, is a 2-wire plug, with a Gray/Black and a Brown Red, on every 530i I can find in diagrams for a 530i M54.

The radiator outlet temp sensor at the lower hose uses a blk/ grn and a black/grey.. The dual temp sensor connection for both a 530 and a 325 are the same Brn/Red and Grey brn on both harnesses.

If you've got a single 4 wire round sensor, I have to imagine an oxygen sensor. What color are the wires, and what year is this engine and harness?

[Liquidarthur]

No, that code is not likely to be related to what has happened at the rear of the motor. What year is the 530 harness and engine?

I have worked on many, many dozens of M54 engined cars, so I'm very familiar with their plugs. Still, there's a;ways some surprise waiting.

Let's go to the code for radiator outlet temperature: This is a plug that's in the lower radiator hose; nowhere near the back of the motor. The "dual temp sensor" at the rear of the cylinder head, is a 2-wire plug, with a Gray/Black and a Brown Red, on every 530i I can find in diagrams for a 530i M54.

The radiator outlet temp sensor at the lower hose uses a blk/ grn and a black/grey.. The dual temp sensor connection for both a 530 and a 325 are the same Brn/Red and Grey brn on both harnesses.

If you've got a single 4 wire round sensor, I have to imagine an oxygen sensor. What color are the wires, and what year is this engine and harness?

The 530i engine is from an 04. Im using the harness from the 325i (03). Perhaps that was a mistake but there was some reason I did that at the time, I don't recall at the moment.

I will double check the color codes and such in the morning and post back.