w204 C220 CDI Camshaft Position Sensor P0340

[starrzo]

Hi guys,

I am hoping for some advice.

I have had my w204 2009 C220 CDI (pre-blue efficiency) OM646 for around 5 or 6 months now. It has been a great car. I noticed when I got the car that it had been running cool so I replaced the thermostat and now the temp sits perfectly at 95 degrees.

There has been one other issue - very occasionally (around 5 or 6 times in total since I have owned it) when the car is idling at traffic lights or waiting at a junction there would be some vibration/rumbling which would go away once the car started moving again. I put it down to possibly worn engine/gearbox mounts, however:

About 6 weeks ago I got a yellow engine warning light - no other symptoms. The warning light disappeared after 3 engine starts and nothing since. This morning, I got the light again. I purchased a cheap OBD2 bluetooth reader from eBay a couple of weeks ago, and I managed to pull the code just now: P0340 - Camshaft Position Sensor "A" Circuit Bank 1 or Single Sensor.

Out of interest, I just restarted the car 3 times, and the engine light has gone again.

So my question is; is it likely that I have a faulty sensor, or is it possible that there are other more serious issues? What should I do now?

I was tempted to run out to the dealer to get a new sensor and try to swap it, but I thought I would get some advice on here first. I have attached two pictures for reference, one of the fault code and the other of the sensor.

Thanks in advance.

 

[AMGeed]

If you trust your code reader to be accurate, then your sensor probably is faulty.
Recycling the engine starter 3 times will extinguish the EML, but if you have a fault, the light will return, as yours has. I'd get the sensor.

 

[umblecumbuz]

... and a code reader that is MB specific.
It will stand you in good stead if you intend keeping the car for a while.

Umble

 

[star]

It's known that some aftermarket code readers give wrong codes, we had one last week that said variable cam timing fault on a snap on reader, only to find it was a boost pressure fault!!! If it's not an expensive part, then worth a risk.

 

[starrzo]

It's known that some aftermarket code readers give wrong codes, we had one last week that said variable cam timing fault on a snap on reader, only to find it was a boost pressure fault!!! If it's not an expensive part, then worth a risk.

Thanks guys.

Yea I'm using a fairly dodgy cheapo bluetooth adapter and free android apps, but I'm thinking that swapping the camshaft sensor should be worth the gamble.

Incidentally, have any of you swapped a camshaft position sensor before?

Obviously I haven't, lol, is it just a simple swap? I had a quick look on youtube and they were talking about making sure the piston was at TDC first, although I think he was talking about replacing the sychroniser as well.

Thanks again.

 

[Yugguy]

Are you sure its 95? That seems hot to me.

 

[starrzo]

Are you sure its 95? That seems hot to me.

Actually, it's probably more like 92, I thought I read somewhere that it was supposed to be 95.

 

[umblecumbuz]

That's the temp that mine runs at. Can't see a problem there.

Umble

 

[Yugguy]

Its just that mine is more around 75 normal driving going to 85 high speed. Do yours stay at one temp regardless? Wonder if my thermostat is dodgy?

 

[EmilysDad]

Its just that mine is more around 75 normal driving going to 85 high speed. Do yours stay at one temp regardless? Wonder if my thermostat is dodgy?

75 deg seems a bit on the low side to me

 

[starrzo]

Its just that mine is more around 75 normal driving going to 85 high speed. Do yours stay at one temp regardless? Wonder if my thermostat is dodgy?

Yea, your stat is on the way out. It should go up to just above 90 and stick there. Mine used to go up and down between 70 and 85ish.

 

[Yugguy]

Feck. I wonder if it is covered under the warranty. I'll have to go down Monday.

 

[starrzo]

Feck. I wonder if it is covered under the warranty. I'll have to go down Monday.

If you aren't covered by warranty it is a fairly easy DIY. Malcolm sent me a useful guide - let me know if you need it. I managed to do it without losing a drop of coolant.

 

[starrzo]

Can anyone help me figure out if I am looking at the correct sensor...I want to replace the intake camshaft position sensor - is the intake sensor the one I am pointing at, which is on top of my OM646 engine block at the back, just under the windscreen?

Code: A0051531328

Assuming this is the intake sensor, I am not sure where the exhaust sensor is, and don't want to replace it by mistake.

Cheers.

 

[starrzo]

Of course I'm being daft cuz this engine has a SOHC?

Watching American YouTube DIY videos always complicates things

 

[Yugguy]

If you aren't covered by warranty it is a fairly easy DIY. Malcolm sent me a useful guide - let me know if you need it. I managed to do it without losing a drop of coolant.

Yeah if you can pm that to me that would be cool. I think it is covered but if not its good to know. Sorry for the thread hijack by the way.

 

[Steve@Avantgarde]

Thing is, those sensors never go wrong, and are only used on cranking, once the engine is running, they bear no relevance, it only measures the crank sensor. You can disconnect it when running and the engine will still run.

 

[starrzo]

Thing is, those sensors never go wrong, and are only used on cranking, once the engine is running, they bear no relevance, it only measures the crank sensor. You can disconnect it when running and the engine will still run.

So you think it would be a waste of time and money replacing it?

Any idea what the issue could be given the code and symptoms I have been getting?

 

[Yugguy]

Is the rumbling/wobbling only when cold? I have read of that being engine temp sensor problem where it doesn't read cold temp properly so slightly misfuels.

 

[starrzo]

Is the rumbling/wobbling only when cold? I have read of that being engine temp sensor problem where it doesn't read cold temp properly so slightly misfuels.

It has actually happened both hot and cold