Hello! If you're tackling the task of replacing your B58's oil filter housing, I wish you the best of luck. This DIY is intense, but after navigating it solo, I believe it's worthwhile, especially considering the hefty shop prices out there. Brace yourself; this job will test your skill.
Important Note: The ISTA procedure is generally spot-on, but there were some details I found missing, making the process more challenging. This thread is meant to complement the official ISTA procedure, which you can find in this directory:
Step 1: Preparation
First, you will obviously need to raise the car in all corners. Then remove all rear engine plastics and the brace. Disconnect all ECU connections on the right side of the engine. Document your progress with photos, and mark connectors for reassembly.
Step 2: Intake Manifold Removal
The intake manifold must come off. Before doing so, drain the coolant from a connector near the front of the car. On my F30 340, it was located towards the bottom of the nearest radiator to the engine on the right side. Expect coolant to drip from various places, so be prepared. Use a penetrant like WD-40 for stubborn coolant quick connections.
Step 3: Three-Way Connector Removal
After the intake manifold removal, take off the three-way connector on the block held by three e-torx 8 bolts. The third bolt may be tricky; a 1/4 socket set with thin extensions was the only way I could get it.
Step 4: Secondary Coolant Pump and More
Remove the secondary coolant pump below the intake manifold but leave the bracket. Remove the transmission heat exchanger, the fuel line bracket, and the wheel well plastic for better access.
Step 5: Tricky Bolt Under the Coolant Nozzle
The most challenging part is the e-torx 10 under the coolant nozzle on the oil filter housing. Remove this bolt first to ease the procedure. This will take some time, so be patient and don't hesitate to take a break to gather your thoughts.
Note: All of these bolts on the housing are captive, don't expect them to completely come out.
Having the new oil filter housing on hand for reference can be helpful in locating this bolt precisely.
The critical tip here is to remove this difficult bolt first. If you loosen the easier bolts first, you'll lose any sight you may have had of this bolt initially, making the entire procedure tremendously harder.
For this bolt, you'll want to experiment with a mix of extensions and a swivel and go in around the lower control arm area, using the transmission heat exchanger real estate for your hands. Fish your extensions past the engine oil heat exchanger, and have a friend watch from above to guide you onto the bolt. Be patient; this might take some time. Once you have this bolt out, proceed to remove the remaining bolts—they are relatively straightforward. There are two behind where the trans heat exchanger was seated, and three easily accessible bolts near the top.
Step 6: Replacement and Reassembly
Replace the housing with the new one, following the reverse of the removal procedure. Tighten the easier bolts first to make the challenging lower one more accessible. Follow the ISTA torque procedure for all bolts, especially on the intake manifold. These bolts are weak and have a low torque spec. Once you have everything cooling related reconnected, I'd recommend doing a pressure test before bolting the intake manifold down to ensure you didn't miss anything.
Sometime along this process you would have drained your oil, go ahead and do a full oil change now by refilling. In my case the oil filter housing came with a filter installed, but double check this before forgetting about it.
The oil system will need to be primed, here is a breakdown taken from dotmaster206 later in this thread:
The procedure is basically to unplug all the injectors and coil packs, and then run the starter motor for ~15 seconds, then let the starter cool for ~20 seconds, then run the starter motor again for ~15 seconds, etc. until you have built enough oil pressure. If you do the procedure in ISTA, it will show a graph plotting engine RPM and oil pressure, and it will tell you when you've got sufficient pressure to consider the job done. If you don't have ISTA, you can just do this procedure yourself without seeing the oil pressure plot and assume it'll take maybe 5 or so "starts" and you should be good
Lastly you will need to bleed both cooling systems. You can do this with some sort of vacuum tool, or the built in bleeding procedures in the car. Kern has a good video for this. Follow his video and repeat the procedures a few times and check your coolant over the next little while to ensure it's fully bled.
Kern's bleeding video:
Step 7: ECU Connector Attention
To avoid issues post-replacement, ensure the ECU connectors are firmly replaced. Simply locking them into place may not be sufficient; these connectors can be finicky. Weird codes or trouble starting may result from improperly seated connectors.
Step 8: Additional Recommendations and Parts
Replace the intake manifold gaskets (part number: 11618637800) and the block coolant connector (part number: 11118619408) to prevent future problems. Oil filter housing (part number: 11428583895). Note, these part numbers are for gen 1, you will want to double check for your car.
Best of luck!