Yes, DTCs 1200 and 1208 are 100% the symptoms of balance shaft failure. The variable valve timing system can compensate, so you'll not experience any performance problems. You can actually drive this way for a while. Eventually, the idler sprocket will wear away completely and stop rotating the balance shaft. You'll get extra vibrations in the engine and a lot of extra noise from the timing chain. This will also eventually damage the timing chain. But this is likely going to take tens of thousands of miles.

 

you need a balance shaft. it needs to be repaired ASAP.

I have seen 2 cars I have quoted balance shafts for come back within a year with no compression in the eng. do some diag and the chain jumps damaging the complete eng.

SO while the eng still runs get it repaired or you will need a NEW engine.

 

Can you explain how the chain jumps timing? I could understand if it were the crank sprocket, but I don't see how idler sprocket wear can cause that, unless it totally wore away.

 

Yes, DTCs 1200 and 1208 are 100% the symptoms of balance shaft failure. The variable valve timing system can compensate, so you'll not experience any performance problems. You can actually drive this way for a while. Eventually, the idler sprocket will wear away completely and stop rotating the balance shaft. You'll get extra vibrations in the engine and a lot of extra noise from the timing chain. This will also eventually damage the timing chain. But this is likely going to take tens of thousands of miles.

Is there any chance it is the camshaft position sensor going bad? I dont have any "noise" and the only performance issue i have is occasional slower than normal acceleration. the CEL has been illuminated for at least 19 months and providing the p1208. Shop wants $7000+ to replace balance shaft (known issue in MB motors for older models, but not my 2009).

 

strange update - i unplugged bank 1 camshaft position sensor and replugged it and the CEL was no longer on after next ignition. Car seems to be doing it's own thing.

 

Welcome to the forum @gregms - please take a moment to read the information on the links below. It explains how to use the forums and update your user profile so that your car's details and your location appear on each post below your avatar. This is good information for others to know when trying to help. It also has good information about how the forums are organized and how to use the search feature:

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If you have a MY2009 car, then you do not have a W203. It it's a C-Class, it would be a W204.