Camshaft exhaust sensor swap

[audipwr1]

Im having a heck of a time finding the right 5mm hex setup to get it on the bolt and also then be able to turn it to get it off

anyone have a specific setup they used that worked?

already had one hex key head into the pan underneath which has been yet to be found

[Str8f4c3]

I usually use a 5mm hex screwdriver bit adapted to a 1/4" drive ratchet using a 1/4" socket (most screwdriver bits have a 1/4" hex so fits right in). Also worth trying to clean the bolt out first with brake cleaner or something similar to make sure there's no gunk in the cap. Hope this helps!

[Stilt]

Im having a heck of a time finding the right 5mm hex setup to get it on the bolt and also then be able to turn it to get it off

anyone have a specific setup they used that worked?

already had one hex key head into the pan underneath which has been yet to be found

Unless I am confusing the two cam sensors, use this little HF 1/4 with the 5mm (or if it's 4mm, I don't recall) and wear some gloves because the clips on the heat shield for the headers will scratch your hands pretty bad.

Use an extension as well; you need to feel where the bolt is with your hand, and then, using your other hand, you'll take the extension and guide it toward your other hand (that is touching the bolt), then put the extension in the bolt for the cam sensor. With your hand still holding the extension, stand up and straighten your back out since you've been bending over for five minutes 😂. Then, attach the ratchet to the extension. Boom, done !

[kaiv]

1/4" drive flexhead ratchet with a short 5mm allen socket.

[y2k_o__o]

Yea the sensor is really situated in very tight space, you need to use a hex bit ratchet

I had to buy that tool to get that thing out, and I nearly rounded the 5mm hex while doing it and I ended up using T30 to get it out, otherwise it turns to a nightmare

The trick is to make sure your 5mm hex is perfectly deep inside and perpendicular ( I know this is hard at the back of the engine, but you have to be 100% sure they are, otherwise you'll end up like me)

Honestly, I have no idea why BMW decide not to use bolt

[maupineda]

I thought about changing he screw to a bolt, but I am a sucker for specialty fasteners and like torx a lot :P

[audipwr1]

1/4 drive with small 5mm hex is the answer

made it change into a 5 minute job

the hex keys were killing me

[sapote]

I just did this today. Got the error code P0017 (camshaft and crankshaft are not synchronized) intermittenly.
This job might look daunting at first, but if you stand at the correct position and use the hands and fingers correctly, it's not bad at all.

I used a 5mm hex bit on a 1/4 drive ratchet, just a standard and not flex head or anything fancy. Here is my experience of how to make the job easier:
Don't use the Allen key as it's almost impossible in this case.
Remove the beauty cover, stuff around the area with plastic bags or towel in case the tool or the bolt fell off and not going anywhere. Squeeze the end of the connector, (located kind of forward toward the right fender, the locking tab is on the bottom side of the connector) and unplug from the sensor, move the harness out of the way. If you can't unplug it then it's ok to leave it connected to sensor. Stand near the drug bin I insert the hex bit into the 5mm bolt first and with only the bit I can make sure it is fully inserted into the hex bolt, then with left hand finger pressing on the side of the bit to prevent it falling out, right hand insert the ratchet drive into the bit. Now use LH middle finger to press the ratchet /bit on the bolt, RH turns the bolt loose. Due to the plays in the ratchet you might only get one click per each stroke due to limited space. But by using the LH index finger to press on the side of the 5mm bit during the CW stroke this will help to take out the plays and you can have 2 clicks per stroke and the bolt will come out in 2 minutes or less. Rotate the sensor a few degrees while pulling, it will come out easier than just pulling. The oring might stay in the hole so make sure to get it out using finger.
So remember: LH between the head and firewall, middle finger pressing the ratchet to the bolt, index finger clutching the bit.
Installation: I reused the oring after cleaned it and lubed with grease, slide it on the new sensor. I cleaned the hole where the oring will sit on the step using a bent brush and gasoline and this ensured no oil leak. Lube the lip of the hole with grease to help the oring to set in without swisting or rolling. Press the sensor until it bottomed. To avoid cross threading: The factory bolt already has a drop of blue Loctite or whatever thread locker on it, and I used a small knife to remove it off the first few threads on the bolt so I can hand thread it straight in and prevent cross threading.

This post is mainly to help me next time when I need to do this job again.