W210 72k kilometres Rattling, Shuddering at Idle
Car vibrates heavily in idle but feels great driving, except for the occasional misfire on the lower gears from stop. The idling got so bad a few times that the car was shuddering. A fuel injector service was performed after each of these two instances and it made the vibration and idle better. This seems to be a carbon deposit issue. Motor mounts, fuel filter, fuel pump all have been replaced under my ownership.
My mechanic isn't going to be going any further with this and I'm tired of spending C$335 on fuel injector service every so often. What do I ask for at a specialist shop: replacement of breathers? Walnut blasting of the fuel lines? Or something else?
Thanks in advance for any insights.


