W203 C180k - Cold - Not starting

[calm9076]

Hi,
Can anyone offer any suggestions please.
My wife tried to start her C180k Coupe petrol (2003) this morning (outside temp -4 degree). Engine turned over and ran but roughly (like on 3 cylinders). She spent 20-30 minutes re-starting the car after it stopped running before she phoned me and I said leave it till i got home later.
Got home tonight tried to start the car and you can hear the engine trying to turn over (doesn't sound like the starter motor) but it simply won't fire at all. I pulled the plugs and sure enough they were soaked so cleaned and dried. Before refitting I turned the engine over and I could see looking down the plug holes the pistons moving up/down (didn't seem to move as quickly as I would expect) so I guess this means the starter motor is working ?? Please confirm.
Anyway, refitted the plugs and tried again but still the same.
You can hear like a slight fire in one of the cylinders when turning over but at no point tonight did it seem or even sound like it would start. The noise when attmepting to start also sounded slightly differently to when turning over normally. I'm pretty sure the battery is OK all-though it's (5-6 years old) and the fuel supply is OK although it may have a lower Octain 95 not 97 like we normally use (my head is all over the place with family stuff). I did do an oil and filter change the weekend just gone (drained from the sump plug) but it has run fine up till today (thursday). I'm pretty sure the -4 is am impact but not sure if the wife's attempts to start for 20-30 mins this morning may have damaged something else.
Any advise welcome.
Having a pretty **** time at the mo and the wife's car is desperately needed so she can visit her poorly dad in Hospice. Been a ****** dreadful year for family and cars 2012. Will be glad to see the back of 2012!

IF you can offer any advise on tests I can do myself I would appreciate it.
If needs be I will get a mechanic involved (Birmingham area if anyone can recommend anyone.....except Andy Gayle!!!).

Thanks ,Chris

 

[grahamcol]

I can recommend a greay Indy in Walsall if that's not too far. ACMS Mercedes. 01922 634666 or 07530 456000, Marc's the owner and you won't get better. Much much better than Andy Gayle's

 

[Alex Crow]

Hard to guess at this one, although slipped cam timing is a worry on this engine...

I doubt you can do much yourself, it seems you have only a little knowledge (no offence intended), so concentrate your effort on finding the right garage to take it to!

 

[cleverdicky]

How is that possible Alex, I thought 203's all had chain driven cams ??
Could it not be a crank position sensor faulty? This cold damp weather plays havoc with sensors at the moment.

 

[Alex Crow]

How is that possible Alex, I thought 203's all had chain driven cams ??
Could it not be a crank position sensor faulty? This cold damp weather plays havoc with sensors at the moment.

All MB cars have chain driven camshafts.
Most of these engine designs see no trouble at all with their timing chain systems.
Sadly some, including this 271 engine, are known to suffer with issues like jumped cam timing.
Although yes, it is not unheard of to have crank sensor failure on a 271 (not commonly though), the failure scenarion is usually very different, almost always being triggered by heat.