OM606 ('99E300TD @ 215K) LOUD AS HELL WHEN IDLE
 

Got a 1999 e300TD at 215k. Had the car for 4 years now, love it to death but when its idling the car is ridiculously loud. Also, when coming to a stop, the motor sounds like its choking/skipping before returning back to idle. I've been told that the fuel injectors need cleaning and I've also read something about air leaks but I wanted to see if i can get any more guidance on the matter. Thanks

Time for an injector rebuild. Not a cleaning but a rebalance and new nozzles from certified shop. Only use bosio or firads. Not Bosch India nozzles.

I appreciate you getting back to me so quickly.
You suggest that I jump right into the rebuild, would there any benefit to cleaning them first? My tech tells me I should start with a proper cleaning.

Mine also seems to be doing this, the stumbling when returning to idle. I also at certain outdoor temps with the car in park and AC not running, it seems to have a miss. I just recently rebuilt my nozzles with Firad nozzles and it was loud at idle, but has since quieted down some. Still a little louder that I would like. Previous to this, I did replace all of the delivery valve seals, clear fuel lines, o rings etc. At some point I am going to go back and recheck to make sure I have the DV torqued correctly just to rule that out. I can't imagine I would have messed it up as I have done many sets of these.

x2 on injector rebuild. Mine does the same at 272K. You could run a diesel purge direct to the filter and it will probably run much better/quieter for a time, but it won't last very long (my experience anyway). There are Utube vids on the DP to filter setup.

Yes I’d highly recommend an injector rebuild. An injector cleaning won’t do a whole lot for a long period of time as treetops mentioned. The MB recommendation is really every 100k have the injectors rebuilt. It doesn’t mean they won’t go longer than a 100k, but the spray pattern won’t be the same and within spec.

Funny I had The same gig going on with my 427k car. I re-replaced all the fuel lines (plastic) and it went away. One o ring must’ve had a slight tear allowing in a little bit of air. The 606 fuel system is the most delicate and sensitive fuel system I’ve ever dealt with in my endeavor of diesels.