CoupeDeta

Hey, im a newbie here. Just picked up my C250 2 days ago, anyway i got a question. Do you guys think it's beneficial to have a turbo timer installed? i'm planning to keep this car for a long time, and i want to find out if there is anything that i can do to prolonged the engine's life, besides the regular maintenance of course.

Thank you.

MBRedux

Actually, the turbocharger is the least of your problems... If I were you I would start worrying that you will need a carbon and valve job before you even clock 50,000 miles.

Reasons?

Your new 1.8L Benz engine is direct fuel injected (DI), no longer port fuel injected (PI). Yes this increases the power band and fuel efficiency, but it is proven to be extremely detrimental on the intake valve system. Severe carbon build-up on the intake valves have been widely reported in all new direct injected engines. Audi, Cadillac, BMW, Lexus, & VW forum sites have been screaming bloody-murder for the last few years about the downside of this new technology. Now it’s Mercedes Benz’s turn.

You see the new USA cafe’ standards demanded that manufacturers substantially improve the fuel mileage. Direct injection was the simplest technique they had at their disposal to comply. Direct injected engines move the fuel injectors from the intake ports (which are before the intake valves) and places them directly inside the combustion chamber thus bypassing the valve system. So the cleaning properties found in most modern-day detergent gasolines never touches the intake valves they’re designed to clean because the injectors are now inside each cylinder! Get it? STP, Seafoam, even BG fuel system cleaners and additives will NEVER clean the intake valves in a direct injected engine.... never. The intake system will need major service starting as early as 50,000 miles (and usually after the factory warranty expires) which is solely dependent on the efficiency of the crankcase ventilation system found in the car in question.

People with new Directed Injected Engines are scrambling to find solutions to this dilemma. There have been class-action lawsuits brought against Audi and are still pending. BMW owners are about to bring theirs... Others are installing Catch-Cans and other make-shift but worthless contraptions to solve the carbon build-up issue on the intake system to no avail. However there are a few companies that have taken the proper steps to reduce the carbon build-up issue by completely redesigning their crankcase ventilation and EGR systems, like Audi.... they did the right thing but it will most likely hurt their defense against the owners of earlier versions of DI engines (2008-2010) who are now demanding new engines/cars in the lawsuit.

The severe carbon build-up can only be cleaned by total dismantling and manual cleaning, otherwise known as a carbon & valve job.

Sorry to be the bringer of bad news... Have fun! Further reading... http://my.is/forums/f104/down-side-s...ystems-431376/ http://www.audizine.com/forum/showth...-up-Megathread

This is what the intake ports of a 2011 2.0L Direct Injected Turbo Audi looks like after just 10,000 miles....



This is a diagram of what a Direct Fuel Injected engine system looks like... notice that the injector no longer sprays the detergent gasoline directly on the valves but directly into the cylinder, so the valves never get cleaned, they eventually just clog up! Where as in the port fuel injected engines, seen in the next picture, the injected fuel cleans the carbon off the valves as you drive.

Direct Injection Port Fuel Injection

CTBenz23

MBRedux I totally agree that as it stands now the direct injection poses a big problem.

CoupeDeta

O...WOW... thx for the replies. MBRedux you know all your stuff, ok so now i understand more about this engine. That picture of the Audi intake port is scary to watch. Now does Carbon & Valve job required by mercedes service? or i have to request this this before 50,000 miles? At what millages do you think, is best to perform this service? i mean looking at that audi engine, it has 10,000 miles and it looks like it's a 100 years old engine.

Thank you.

MBRedux

This is hard to say given that Mercedes has only now started making DI engines. Most likely they will follow the same pattern as their competitors and only honor repairs if necessary during the warranty period. But even then or if you have an extended warranty, Carbon & Valve jobs can be denied if THEY believe the issue hasn't severely impeded on the engines performance.. So keep records of your fuel mileage and engine power. As the carbon builds up, you will notice rough idling, poor performance, and poor mileage... only then will you qualify for warranty repairs. If your car suffers from these issues AFTER the warranty is up, then you must foot the bill.

Mercedes will NOT perform a carbon & valve job as part of their routine maintenance schedule.


PS: With this all in mind, there is a possibility that Mercedes has taken the necessary steps to reduce the carbon build-up issue... just like Audi recently did. That is, to drastically improve the breathing capacity and the oil separation of the engine's crankcase and exhaust gas contaminants ... So if they have, then the issue is less severe than it appears. Only time will tell.