2010 X5M. It all started with valve cover gaskets. Oh Boy!!

[Jaydee99]

I am posting this In hopes it will save others some of my most frustrating moments. I am the second owner, I bought it at about 140k Km (87k Mi). This was a very long project, starting in April of 2022 and with the engine finally running well in February of 2023 (I had elbow surgery in the middle). I am a licensed HD mechanic in Northern Alberta Canada. I have ISTA+ and so had access to all the mechanical procedures, torque specs etc. It was a steep learning curve for me, I have done a lot of domestic auto work early in my career, however BMW/German engineering is different from the domestics.

It started with valve cover gaskets. They had been leaking for about 3 years, slowly getting worse. Every time I parked in my garage it stunk of burning oil. I was also slowly losing/burning coolant. The stealership wanted $3800CDN?? for the gasket replacement, it turns out the procedure is to drop the engine/trans sub-assembly out as the engine compartment is very snug, so the cost does make some sense. I started the VC removal process and in the process discovered the source of the coolant leak, 2 actually, the temp sensor port in the bottom rad hose was cracked and the tiny 3/16 air bleed Y that goes between the heads to the DS CAC had also broken. This made a horrible mess in the 'Hot Vee'. Plus a rock had hit the CAC main rad bottom front, I took it to a local rad shop and the welded over the pinhole for $65.

I decided to pull the turbos, Cats, and exhaust manifold as I thought I had heard an exhaust leak at times. Everything was fine in terms of a leak BUT...I saw signs of the valve stem seals leaking in the exhaust ports, especially on bank 2 (DS). I did some research and discovered that a drawback of Direct Gas Injection is that there is no natural cleaning action in the intake ports and that the would likely be much worse than the exh ports. I don't have a hoist or an engine table so I decided to just pull the heads off. This is difficult but not impossible. I had to undo the intake manifolds including the mounting studs and they stayed in the engine bay when the heads came off. The intake ports and valves were disgusting!! I inspected the timing chains, they looked Ok, the slides had very little wear and the chain and sprockets were also fine so I decided to reuse them. They had been previously replaced by the PO.

Parts ordered and start the clean up. In retrospect I would have gotten the Heads hot tanked as they took quite a bit of cleaning. I had access to our Varsol tank at work plus I used carb cleaner to soften the deposits in the In/Exh ports. I used the wire wheel on the valves themselves. Valve guides/stems were in spec. all good there.
I got the rest cleaned up with varsol and engine degreaser, it really did well on all the hardened coolant mess in the vee and all the other parts of the block.
Parts arrived and started the reassembly. There are a few tools necessary to Disassemble/Reassemble everything. I needed a deep pocket valve release tool $35 and Cam timing tool $$85 (Amazon). I also needed an injector remover/installer tool $125. I got that from my parts supplier (FCP Euro). My injectors were index 11, and 12s are about $4500US so 11s it is!
So all back together in about Sept and...it runs like a bag of crap, multiple misfires, running on about 4 cylinders on both banks! I love it when something comes in running fine but leaking and then no leaks but now it won't run!?!? arggg. What The Frac!!!

A word of warning! When it says in the cam timing procedure NOT to turn the engine opposite normal rotation...THEY MEAN IT. Ha. Exh bank 2 went way out of time, thankfully even thought I ran the engine no valve damage occurred. So valve covers back off and retime the cams. So now what?

I checked plugs and coils, all good. I checked power/ground to the injectors, all good. So was there engine damage? Compression tested all good, Cylinder leak down? All good. I would get intermittent cam sensor codes but the one throwing codes would change plus I had a new sensor and it didn’t make a difference I think the codes would go active because it ran so badly. Low oil pressure? Measured with a manual gauge, it was good too. I was stumped.

Here is a hint Battery disconnected for months and the injectors in the S and N63 engines have to have fuel injector trim codes programmed in. Apparently they arn’t permanently coded in the ECM and require battery power to keep the coded in memory. Luckily I had taken pictures of the injectors before I reinstalled them so all I had to do was program them in with ISTA. Eureka the misfires all went away! BUT it still wasn’t done with me. I had one active code left. Exhaust cam bank 1 was not responding to VANOS. The control cartridges are a pain to get to behind the CACs, especially the PS, that one bolt is a PAIN!! So one evening I tried the test plan for the VANOS code, part of what it does during the plan is to “purge” the oil circuit for the VANOS actuator. I did that procedure twice and voila the engine runs smooth and the active code is gone. Yay!!

So now I drive it to work for about 3 weeks everything is fine and BAM. Whenever I put my foot into it a bit I get stumbles/misfires and the CEL is on again. Now What!?! I connect ISTA again and find “Charging Pressure Sensor Bank 2” code is active. I completed the test plan in ISTA for it and sure enough it is reading pressure but too low. Sigh. So one more parts order, regretfully there is only BMW original available for this part, no OEM or OE versions. Thankfully the sensor is relatively easy to get to on the front of the CAC. Installed and back to full 620 HP (DINAN Stage 1 and Eisenmann race exhaust from PO). Hopefully that is the last of repairs for a long time. I hope this can help someone if they are finding a tough misfire diagnosis happening to them.

[jimoreno]

Wow, just wow! That is a lot of work. I'm about to start doing something similar to my N63 engine. I've got a valve cover leak, I found that one of my turbo wastegate flap has a ton of play (no codes yet) plus I want to change all of the turbo oil and coolant hoses plus PCV stuff. Since I have to take coils out I'm replacing them plus spark plugs (it has 109K miles).

It is a lot of work just to get to the valve cover gaskets! Just ordered the injector remover from Amazon.
One question, did you replaced the injector Teflon seals? If you did, what tool did you use?

[Jaydee99]

I did replace them and don't forget the Coupling Elements as well. Here is the link to the tool I bought. It includes the installer sleeves.
https://www.fcpeuro.com/products/bmw...m-b130270kplus

[jeep]

Kudos on some serious work on that X5M! I wish I had half the chops.