[01LagunaSecaE46]

We endeavored to replace the exhaust side cam sensor today and got it done, but only by the virtue of my friend's dainty hands and deft fingers, as well as a willingness to sacrifice a few skinned knuckles and nearly dropped wrenches.

This is the first repair i've done on my E46 M3, and it amazed me how stuffed into the engine compartment the engine really is, it's crammed in there. even getting a visual on the part in question was difficult, owing to the cabin air filter in the way, which had to be removed by way of four T-30 Torx screws. once that was out of the way, the part could be seen -- barely, by looking straight down the firewall on the exhaust side of the camshaft cover. the 5mm hex bolt is at about a 45 degree angle to the motor, so prepare to attack it with your left hand coming in from the top, and the right coming in above the exhaust manifold toward the back. it is the right hand that does all the work. with a short-arm 5mm hex key, it is just possible to get enough rotation on the bolt to insert the key again for the next turn. its VERY tight. putting the bolt back in without dropping it takes a little meditation, and some Bourbon to steady your hand if necessary. do not drop this bolt.

The new sensor will likely be larger than the one you remove. dont let this faze you, as the newer BMW factory part is different than the original, it is larger. im thinking that they beefed up the part, and i'm glad they did, as im not looking forward to replacing this one again any time soon.

Use a new O-ring (of course) as the one you pull out of the head is likely brittle like mine was. it was nowhere near as pliable as the new one, and this is a crucial oil seal, so make it right.

We reset the service light, and gave the car a good romp, and the light remained off, so we're declaring a success and urge anyone with small, nimble hands and a 5mm hex key to pursue this option rather than pay the stealership or private mechanic to do the job.

I'd have taken pictures, but everybody knows what the part looks like, and it'd have been near impossible to photograph where the part goes.

[tr0mbley]

This was a good post for my problem. I've had my SES light on for about 10K miles. I honestly thought that this light was triggered by mileage or driving style, and upon reaching a certain odometer reading, you were urged to go directly to your nearest BMW cash register and open your wallet. I thought the light was telling me to change my oil (which I had already done) and I simply didn't know how to reset it so I left it.

Need to get my emissions done soon, and this light was going to present a problem. Took it to Autozone, scanned the DME, and it found P0014, 0017, 0365, and 0420. Did the research, found this post and others like it, and decided to tackle this myself. It's a tough one. I actually had my wife attempt to run her hand along the exhast shield toward the bolt and turn it loose. No dice. Soon learned that I needed a long 1/4 drive ratchet with a 5mm hex on the end. Was able to get a few clicks in with each turn and finally got the bolt out. In my case, fresh Busch Light was applied liberally to steady the nerves during bolt re-entry. Same tool used, with a tiny little turn each time. If I had a better ratchet that was half the size, it might have made quicker work of the job. I also had to remove the rubber wire guide on the exhaust side on the back of the valve cover. That thing is a bastard. All the wires were in the way and had to move. I did not remove my A/C lines, just didn't see the advantage.

It's a back breaker for sure... again.... heavy doses of Busch Light to ease the pain.

One question: what the hell does this thing do? My car ran fairly good without it. Plenty of power, thrilling launch control sessions with friends, great handling... so what does this really do to the camshaft? I did have some problems like choppy morning starts, sometimes it wouldn't start on the first try, it stalled a handful of times, and there was some hesitation when first taking off. Will these problems be solved? I also cleaned the MAF sensor. I must say, the first spin with the car after performing both these tasks was incredible. Kind of like shooting a polar bear with a BB gun right in the ass. I mean the car just floored me. So what does this sensor actually do??? And if I don't reset my SES, will it go off automatically?

[tr0mbley]

Apparently the exhaust camshaft sensor makes the car start better, idle smoother, accelerate more evenly, and just helps the engine stability and performance in general. Restarts are consistent. The car just runs like a champ now. It must have something to do with timng/engine management. And today after lunch I noticed that the SES light had gone off.

So replacing the exhaust camshaft sensor cleared generic OBDII codes P0014, P0017, P0365, and P0420.

[MY02M3DINAN]

I did my exhaust cam sensor today.... and it was not fun.

Having a few years of experience on MG and Triumph TR products gave me the patience and tough skin necessary to tackle this problem. I had to trim an allen wrench to make it just a tiny bit easier. But overall, I feel good that my stealership did not get my money on this one!

The car idles and runs much better now.

[coolmody]

I replaced my exhaust cam sensor twice because I was throwing the P0014 and P0017 codes (no P0365 or P0420 codes however).

Had my whole top end of my VANOS replaced, and I also just recently replaced the VANOS solenoid. I'm still throwing the P0014 and P0017 codes. I'm experiencing the same symtoms you guys are.... weird idles, stuttering starts, hesitation.

Any ideas on how to solve my problem? Should I try the intake cam sensor? About to give up here soon....

[Dustyice]

Sorry to bump such an old thread but thought it was better than making a whole new thread.

Do you think that my cam sensor could have been knocked off by my Indy shop when i recently just did my valve adjustment? It has only been about 2 weeks since I got my adjustment done and my car has been idling hard, shuttering and I pulled these codes?

I am going to take the car back Monday and want to go in with some knowledge.

Thanks in advance!