Hi All. Some who know my history, know I bought a 2007 GL450 with a bad headgasket. I have completed the repairs on the headgasket, and the truck runs perfectly now. Unfortunately, I get a niggling code that is kind of driving me senseless. It's P0016 (Right intake camshaft position out of correlation with crankshaft position sensor). Unfortunately, because it runs perfectly, I assumed the best - that I had done something to the sensor or the magnet, so I replaced those. Before I did so, I checked that I had correctly timed the engine by rotating to 305 ptdc, and using the view windows with the sensor on the pulse wheels to ensure the engine was in time. It's bang-on perfect across all 4 camshafts. The issue went away for a week, and then returned after replacing the magnet. Parts were genuine MBZ. I also swapped intake and exhaust sensor - it persisted on the intake. I also tried cleaning the connectors with electrical cleaner, thinking that might be the issue. No dice.

This weekend, I finally got around to connect with my Star diagnosis, and went through the diagnosis. It led me down the path of pulling the right cover again and checking the intake camshaft adjuster to see if it had twisted. It's in perfect shape, so that's not the problem.

The star diagnosis now says I need to do balance shaft repair... ugh. I am very skeptical of this - I am both weary to do this job (because of the time involved, and because , well, wouldn't the timing be off in the view windows if that were the case?

Before I start throwing more parts, or god forbid, do the balance shaft, I wonder if there are any ideas, none of which seem really that great in my mind. I have some thoughts I could try before I do that.

1. Is it possible the crankshaft position sensor is bad? Wouldn't that throw more than just P0016 (MBZ 1208) code? I'm trying to wrap my head around this - no trouble starting, it fires right up, runs smoothly, perfect.
2. Is it possibly the oil control valve? Wouldn't I get a P0011? Is there a way to test this?
3. Is it possibly, god forbid the wiring to the intake sensor or the crankshaft position sensor?
4. I already changed the oil after the job - is there a need for another oil change?
5. Is there something else? Is it possibly because it just hasn't been driven enough after the 2 months of repairs? Does it need more road time?

I'm just stumped, and hoping the collective brain power here might have a thought on what to chase.

Thanks for your help!

 

I don't know much about your history with the car and the repairs you've undertaken. My first thought is timing chain - the chain itself, sprockets, guides.

Not too long ago I came across an article which was chacing after similar problems, but it was not in an MB.

https://www.picoauto.com/library/cas...-warning-light

 

Thanks, Explorer - I find that example surprising - perhaps representing a similar case as mine. There were no deviations in timing through the inspection ports, like my engine ,but it nevertheless triggers the error code. I personally lack the diagnostic abilities or equipment the writer has available, so i'm kind of shooting in the dark. If I cannot find a simple resolution, I think paying for a diagnosis is my next best bet. Thanks for your answer.

 

No problem. Posts like yours add to the normal and sometimes mundane problems we encounter and make for interesting reads. I'll be following your progress with interest.

What made an impression on me were the similarities between your case and the one in the article. My diag skills are way below yours or the author's, I'll be the first to admit that. If it was the chain or related parts, getting to them is no fun and takes a significant amount of work and time. I agree with you that it's better to diagnose correctly before a deep dive into the motor again.

 

Hi acsavage,

Just came across your thread and was wondering how it all turned out?

I have a 2008 GL550 and quite the similar problem. A p0011 error code came up - I had all camshaft sensors and magnets replaced - error went a way for about a week and then it's suddenly back (but only occasionally). All details here: https://mbworld.org/forums/gl-class-...-bank-1-a.html

Would be awesome to hear how you resolved the issue. After all we basically have the same engine (m273).

Cheers from Canada
Seppone

 

M273s seem to be more prone to cam timing related error codes as they age. I replaced the cam magnets many times on my GL550, and the replacements became more frequent once I hit 200Kish. I saw speculation somewhere that as the timing chain and sprockets wear, the timing changes enough to trip error codes occasionally. New cam magnets seem to fix it for awhile, but the codes eventually reappear again (a year or two in my case toward the end of my ownership). If the codes bother you, at least the magnets are reasonably cheap, and with the exception of the one behind the power steering reservoir, easy to change. You might try swapping cam magnets between the intake and exhaust cam to see if the error code follows. Not really a solution, but P0014, 11, 21(the one you don't want to replace) and 24 codes are pretty common as M273s age. I'll attach a diagram that I've referred to many times over the years to determine which one is acting up.

 

Thanks, @EWT for your explanation. Sounds plausible to me.
In my case, I don't believe its the sensors or magnets since all 4 have been replace at once.
So why did you not consider to change the timing chain?
I found kits with the chain and some sprockets for around C$570, like this one: https://partsavatar.ca/ina-timing-chain-kit-zc0094k
Labor comes on top - so not cheap, but also not unaffordable.

The other questions is: What will happen if I just leave it? I mean it probably won't rip...

 

Replacing the chains and guides probably is the solution, but I had 250K miles on the vehicle, had already purchased another vehicle with a M273 (11 ML550) and it is a big job (IIRC, book time is something like 25 hours). It just wasn't worth it to me to put that much time into a vehicle I wasn't planning to keep for the long term. If it is the chain/guides, eventually the chain will skip and the engine will likely bend valves at a minimum, but it doesn't seem to be something that occurs quickly once the cam timing warning start.