LeonF

Since recently I have become a proud owner of a 2006 CLS 55 AMG IWC Edition. And the car is in flawless condition.
Nevertheless I did what any owner would do and did an Engine Oil change, Transmission Oil Change with the electrical connector. But recently after owning it for about 2 months I started to realize that when I floor it, and it gets to higher rps 5000-7000 I find myself creating a massive black cloud behind myself. Doing some research I found out that it is nothing to worry about and that the engine is running rich, burning excessive fuel. Seeing that day after day I now noticed that I don't hear much of a S/C whine. Which I never really noticed as even without a S/C it puts a smile on my face when I floor it.

I'm trying to put everything together now and figure this out, as it's creating the black clouds because it is probably not getting any boost from the S/C right now. The Belt is not slipping and pulley is turning. It does have a smaller pulley and a VRP heat exchanger from the previous owner. Can someone tell me what might be the issue?

I would love to see that ESP light flash again.

AMGPilot

When were the spark plugs last replaced?

LeonF

That I'm not sure, but I am not getting any misfires or codes. It's running like an M113 at the moment but it's supposed to be an M113k.

GinDistiller

First step is to get a scan with STAR for any engine codes, not just generic OBD2. Then you should datalog - what are the IAT readings, short and long term fuel trims, boost/vacuum levels etc. This should hopefully give you a direction to go.

LeonF

I am currently running an OBD2, cause that's all I got and I'm looking at my stats when driving. Here is what I saw for boost. When cruising at 100km/h I have -8 to -9psi boost. When accelerating slow I get -2 to 5 psi boost. And from hard pulls I get anywhere from 9 to 11 psi boost. I dont know how accurate the OBD is but that is what I'm getting. If it is correctly reading it than that means the S/C should be providing boost. But I don't hear any S/C whine. And I am still getting black smoke from the exhaust from flooring it. But I noticed that it only gets black smoke when I floor it.

GinDistiller

If accurate then those numbers are fairly normal, not sure what size pulley you have but if the SC wasn't engaging you would be hitting a wall at 0 psi under moderate and heavy acceleration.

You should be able to look at IATs, if your sensor is bad and reading very cold air coming in it could be dumping fuel. And you need to look at the fuel trims to see if the car is actually signaling a bunch of fuel to be dumped, or if it isn't noticing the extra fuel and thinks things are normal. You should have long term fuel trims under 5%, and short terms should jump around but not really go over 10% in either direction, this can vary based on what tune the car has.

If you can't get access to a STAR, I would at least buy an iCarsoft MBII scanner that can scan the actual modules, more than likely you will have a code in the ECU pending if there is something going on. Too many things it could be to start throwing parts at it. And these cars don't really make an SC whine like other supercharged motors do, if you have an aftermarket intake they will, and there are some engine bay trim pieces you can remove from the hood to increase SC noise, but don't expect a classic muscle car blower whine sadly

If you don't have any previous maintenance history, you may want to replace plugs and front O2 sensors anyway which could possibly contribute to an issue like this, but are definitely important maintenance items regardless.

bbirdwell

FWIW, I get no supercharger whine on my car. And I know I am getting full boost. Supercharger engages at half-throttle.

If you don't have STAR, get it or equivalent. You can literally test the supercharger clutch circuit while standing next to the car. And the intercooler pump. And the SAIS air pump. You can check the health of the transmission clutch and brake packs. You can read out the estimated SBC pump lifetime and properly bleed your brakes. You can test almost any digital circuit in the car. etc, etc, etc. You cannot afford to not afford STAR. Otherwise you will be chasing ghosts while wasting your valuable time.

LeonF

Where can I find one for a decent price that will let me do all that? And will it let me adjust and tweak components? I took of the Air filter and Mass Airflow Sensor and sprayed 2 full cans of Sea Foam to hopefully clean out all of that carbon buildup I have and poured 2 cans into the fuel tank. Hopefully that will help but I have low hopes. It's still creating black clouds behind on hard pulls but only when clicking through the throttle pedal and going above 4500RPM's. I am getting 10-13PSI boost when hard accelerating so the S/C does engage and is making more than enough boost. But I still have no clue as to what happened to make is start creating black clouds.

LeonF

And what are the "IATs", what can I do or find out with those numbers?

machild

IAT = Incoming Air Temperature

There is a sensor that if failed (and they can or at least get lazy) that will directly impact the performance of the SC. Do a search here you will find more to read than you will have time for.

LeonF

I have the Intake Air temperature that I am looking at. From what I remember that shows 40° or so when it's +30° outside on a drive. I'll get exact numbers today when I take it out for a drive.

LeonF

So my intake Temps show a little higher than it is outside when driving and they increase when accelerating. I dont know if it's supposed to be like that.

kevm14

That is normal.

GinDistiller

Yes your IAT numbers seem ok if that is what they are, it's when that sensor reads the air as super cold when it isn't that it will dump fuel in the map. STAR is best found used on Ebay, most are Chinese knock offs but they work ok, it's a risk buying them but you really can't find Genuine units (someone correct me if that has changed) or if you do they are almost as expensive as the car itself. Yes you can tweak certain settings but not like tuning, it is mainly to run the complicated and car-specific diagnostic tests like supercharger clutch, throttle actuations etc. And you'll need it if you ever want to flush the brake system. I got my STAR setup for about $600 if I remember which is pretty standard. The iCarsoft MBII won't do any testing, but will get you codes that OBD2 won't read and is a little over $100, so that is at least an option to get more data to solve your problem. Ideally you'd get a STAR, or go to a Mercedes shop that has one for a scan.

I'm guessing you didn't actually pull the Mass Airflow, our cars have MAP sensors that are on the side towards the bottom of the supercharger and are a massive pain to change out (and you shouldn't clean them). If you removed the sensor behind the supercharger on top of the aluminum 'y' that is actually the air intake temp sensor we were talking about. Probably didn't hurt to clean, as long as those readings stay the same (about 10-15 above ambient).

Do you have any other mods on the car besides pulley and heat exchanger? And have you looked at your fuel trims while driving to see what the percentages are?

kevm14

I still think a Launch x431 product would go a long way as a general tool. Is there anything that can do module reprogramming that's aftermarket? MANY aftermarket tools can do module reprogramming in general, but not sure about these cars.

LeonF

It has a Stage 2 Power Package that includes a larger VRP intercooler and BOSH high flow pump, 550cc injectors and a smaller pulley on the SC, don't know the exact size. I recorded some values at 100km/h cruise and from hard pulls to hopefully narrow down as to what it could be. I'm planning on taking out the injectors and spark plugs tomorrow and give them a good clean to narrow it down further as to why it's making black clouds on hard pulls.

Here are the links for the videos.

At 100km/h cruise set:
At hard pulls: