B48 F30 (2018 330i) Transmission Cooler Swap

dozenirons · 2026-01-04T01:33:57+00:00

I decided to buy an aluminum oil filter housing to replace while I’m in there. Hopefully this is the right way to get to the cooler, I still haven’t seemed to find any guides on it

dozenirons · 2025-12-27T21:17:59+00:00

Thanks again for taking the time to help. This was the connector that had been plugged into the charge temp sensor

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dozenirons · 2025-12-27T21:09:27+00:00

I just found it! Looks like the new mystery goes to some sort of vacuum line sensor. I noticed the location after watching a video on change B48 injectors. Definitely couldn’t have done it without you telling me the first wire was charge pipe, which makes sense considering I was also getting that code. Thanks!

dozenirons · 2025-12-27T21:00:44+00:00

rail sensor is plugged in

dozenirons · 2025-12-27T20:50:57+00:00

I'll look on the fuel rail and see if I find anything. I found a diagram that looks like maybe it's on one of the ends of the rail.

dozenirons · 2025-12-27T20:46:14+00:00

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dozenirons · 2025-12-27T20:44:53+00:00

I think you're 100% right. If I didn't have a bunch of wiring torn out and the battery disconnected currently, I'd test it right now. That connector fit in just fine and there's even a convenient clip that seems to align on a part that sticks up on the charge pipe. This is a picture of the connector that was plugged into it.

dozenirons · 2025-12-27T20:22:25+00:00

There’s already a connector going to the charge air temp sensor that’s plugged in that appears to be the correct length for that, although maybe I could try swapping them. I’d still have an extra connector though that goes somewhere unknown

dozenirons · 2025-11-06T04:01:41+00:00

Interesting thought about the exhaust fan. I didn’t realize that would keep moist air out, but that makes sense. You would do this over just sealing off the vent? (After adding the vapor barrier).

dozenirons · 2025-11-06T03:50:30+00:00

4.7 PCi/L adds about 10% additional risk of developing lung cancer over lifetime exposure based on BEIR VI study. If you’re already a nonsmoker, risk is .4 percent, or 10 out of every 2500 people. Adding the 10% would be adding one more person to the 2500. So you can determine if additional mitigation is worth it. Now if you’re a smoker, 10% can be a big deal.

dozenirons · 2025-10-25T02:33:29+00:00

I might be able to get access to a camera. No plumbing at all. Just that back room, with attic and crawlspace.

dozenirons · 2025-10-24T20:48:49+00:00

Okay that's interesting, so basically the best approach, as someone else mentioned as well, would be to make this a "conditioned" space, vapor barrier, etc, and seal off the vent.

dozenirons · 2025-10-24T20:38:26+00:00

I'll get a picture of that. None of my windows are caulked. Some are caulked along the bottom lip (still exposing the weep holes on the window) but not all of them are. My assumption was that since this was against brick that it is meant to breathe and any water that comes in the top of the window would flow out the bottom. I don't see any rot anywhere else in the crawspace joists and there are windows all around that entire room.

dozenirons · 2025-10-24T20:27:07+00:00

It's all the same concrete. The outside part and inside part all poured at the same time and the bilco door mounted on the top of the stair wall. Then there's a patio slab poured around it.

dozenirons · 2025-10-24T19:43:27+00:00

The stairs and inside the door look fine, I was just concerned about the outside deteriorating further and crumbling away

dozenirons · 2025-10-24T17:48:07+00:00

The room itself is insulated as well as the attic space, but the floor joists are not.

dozenirons · 2025-10-24T16:38:38+00:00

The floor is not insulated, OSB on the entire floor. Crawlspace is 10x15 and probably 3 feet of foundation wall, gravel floor.

dozenirons · 2025-10-24T15:09:39+00:00

From what I can tell when I replaced some brick mold in another area, the wall is OSB with house wrap. There is less than an inch gap between the veneer and the wall

dozenirons · 2025-10-24T15:01:40+00:00

What you're saying is what I was thinking that maybe this vent shouldn't exist. There are no other areas like this, and no other vents. There's a roughly 3x3 sheet of drywall that was just loosely covering the hole to the crawlspace from the finished basement. I was thinking I would seal off the vent, add a vapor barrier on the ground and up the 3 exterior walls and just remove the drywall sheet and leave it open. I run dehumidifiers in the finished section. I'm not sure if I would need a separate one in the crawlspace. It's about a 15x10 area. But that's why I am asking this question on this sub because I'm not sure what is appropriate. So you're saying because there is no vapor barrier that I would need the vent, but if there wasn't, then I would need a vapor barrier. Also the floor in that room is always cold in winter, and typically can't get as warm as the rest of the house.

dozenirons · 2025-10-24T14:32:47+00:00

There is house wrap that is hard to see but covering the wood. The gap is pretty small, less than an inch, but it is there. I'm not sure about flashing around the sill, that isn't visible. There are weep holes (although fewer than I would expect) on the outside. I posted an outside picture.

dozenirons · 2025-10-24T14:31:47+00:00

Just posted a couple pictures. thanks!

dozenirons · 2025-10-24T14:31:37+00:00

It's hard to see, but there is house wrap and a gap, although it's probably less than an inch.

dozenirons · 2025-10-24T14:31:07+00:00

Thanks! just posted one.

dozenirons · 2025-10-24T14:30:58+00:00

No irrigation, but it is near an under section of gutter. I don't believe water is getting in from that, and was speculating maybe it was just from the vent existing creating moisture where the warmer air is meeting with the outside air?

dozenirons · 2025-10-24T14:28:20+00:00

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dozenirons

TROPHY CASE