I'm not very car savvy and I just bought my 2005 C230 K Sport. So please bear with me! I have about 105,000 miles on it.

Just yesterday about 15 miles after I filled my tank from total emptiness, I noticed it lost A LOT of its power. It still runs normally, just doesn't accelerate near as fast, and sounds as if the high pitched winey noise from the supercharger has faded.

So I assumed the supercharger is the issue and spoke with the guy at the used euro cars dealership and asked if it needs to have its own oil replaced, and he replied that it uses the same as the engine although I feel like I've been reading otherwise. Then I called my local Merc dealership and asked if it just needs to be replaced and he said that's not something you need to do and I've also read otherwise. So I'm totally lost. Please help, my main concern is what your highest possible price estimate on the repair may be. Lowest?

 

Big Hint: Tank was empty. Possibly you just sucked up all the crud on the bottom of the tank and plugged your fuel filter. Has it ever been replaced?
Don't jump to conclusions.
The dealer will charge you 3 grand to replace your supercharger, and I'm sure they'd be happy to even if it's the not the problem, but I'd bet it's not that. Especially since it was fine till you filled the tank...and with what I might ask? 87 octane will drop a lot of power on your car.

Check some thread on fuel filters. If you aren't savyy, maybe just order the part online for about 3-40 bucks, and have a local mechanic fit it for you. It's not hard, just messy. 4 hoses and one bolt.
But at the same time one spark, and you go boom. Don't do in a garage where a water heater's gonna fire up. So, while it's not hard, serious caution is required when doing it. One little static discharge...well you get the picture.
Replace the filter, top up with some quality fuel and run a bottle of techron though to clean the fuel injectors. Paypal me 10% of the money you didn't spend and we'll call it even.

Find a good indy mechanic, not the dealer.

If the supercharger is busted, a rebuilt one can be had, or get one off ebay, send it out for rebuild
(or takes your chances) and it takes a couple hours or so to swap it. And you can sell your core to someone who needs a rebuild.
It's just an air pump ya know.
It's bolted to the outside of the engine. You remove a few pieces and the belts, and unbolt the old one, bolt on the new one. Not a major repair.
Don't let the stealers screw you.

Otherwise there is a multitude of electronics and valves that control the flow of the air, and hoses too. No way is your supercharger busted.

 

My tank had about a thrid of a gallon left before I filled. If I filled it with anything other than the 92 octane premium I've been using, then it was a mistake and didn't realize it. Fuel filter WAS my first guess, but I figure the car might be a little sputtery if that was the issue, also, I'm not sure of the last time it was replaced =/

So that considered, the fact that I do make use of the cars speed pretty often, and that the noise the SC makes seems to have deafened, led me to believe that must be the issue.

So this is where I'm not car savvy. I don't even know where on the engine the SC is located or what it even looks like, let alone where the fuel filter is located.

But I sure hope you're right about the fuel filter, I'll have to give that a shot. Probably nowhere that sells the particular one for my car in store is there?

 

I agree that it doesn't sound like the fuel filter for the reasons you gave. Since you're not hearing the whine, it sounds like that could be what's happening but there could be less expensive reasons for your predicament that should be investigated first. I assume since you didn't mention any other events that you didn't loose the belt (I think there's only one and if so, you'd know). I wonder if there is an electrical switch to the SC. You might check your fuses. I don't know specifically but IF you did have low octane gas in the car, the super charger might be shut off by the knock sensor. If you can stand it, if you think there is any possibility that you have low octane gas, you might want to run that out and replace it with premium first to see if that helps. I've never tried anything but premium but from what I've read elsewhere on this forum, using mid grade will work but the reduction in mileage and power negates the cost advantage.

FYI - the SC is under the air cleaner housing on the driver's side of the engine. The fuel filter is near the driver's side rear tire under the rear seat under the car.

As Sport Coupe said, find a good independent shop that specializes in MB and take it there. Don't go to the dealer - you will likely be reamed (but you get a free car wash ).
Good luck!

 

drive until theirs nothing in the tank then put techron fuel cleaner in...then fill your tank to full with shell

this definatly works for my car and i can feel the dif after

 

I don't even know where on the engine the SC is located or what it even looks like

 

Did you read my post above?
To narrow it down, it will have a pulley on it.

 

It's never going to stop, is it? You're going to be a troll forever.


OP - The S/C spins at all times with the engine on the C230K. It can't clutch in or out like on the C32, for example. Perhaps the actuator that releases boost is stuck open? I can't think of the right term for that at this moment.

 

OP and Forrest errr Sammy are made for each other.