Mathieu_AMG

So today I had a fun trackday at "Circuit de Mettet" in Belgium, organized from the dealer where I bought the car.

First of all, the C63 is not the ideal trackday-car. It's to heavy, to much understeer, ... But it's fun to drive :-)

So the sessions were 15 minutes, the first 7-8 minutes, no problem. Suddenly I got a black flag, I thought it was because of the noise-limit or the drifting, but they said my car was smoking...

I checked the car, no oil leaks, no power loss, normal oil and water temperature, normal oil-level.

Next session, I do a warm-up lap and start getting on the throttle, constantly checking my mirrors for smoke. No smoke, everything ok. After 10 minutes I'm taking a slow left, just before the straight and going on the throttle, there's a lot of smoke, really a cloud of smoke that I can see on the track after me. During the straight line, no (or little) smoke.

I asked some friends, from what they say, it's like that the car is smoking when going on or off the throttle (just before - after corners). Really a lot of smoke (probably more than what I can see in the mirrors).

I stopped tracking the car and went home. No problems at all, did some high speed runs, no smoke at all, nothing.

I am pretty sure, when I go to the dealer, they will find nothing. No error codes and when the car is used in normal conditions, you will see no smoke. No point in opening the engine when there is nothing wrong!

I still have six months warranty left, but I'm afraid this is the start of a bigger problem, that I probably will have in 7 months :-(

Has anyone experienced this?

jrcart

Crankcase ventalation, blowby...... you need a Weistec oil seperator catch can. Fairly common issue with these motors especially when run hard at WOT. Open up your airboxes and remove the filters and check out the bottom of the airboxes, I bet you a dollar there is a puddle of oil in there. I run thier oil seperator on my cars, great product.

They were offering a group buy discount on here a month or so back, not sure if they are still doing that or not.

Mathieu_AMG

Thanks for the advice, I'm going to check the filters right now ;-)

I have to say, there were 3 other C63's present who didn't have this problem. One had the MCT transmission and went into limp-mode after 3 laps. The others didn't have the smoke problem. I did previous trackdays on faster tracks (Spa-francorchamps), also without problems.

I always let the car warm up slowly, do cool-down laps. I drive fast but I am not the type that will abuse his car...

Is there an explanation why I would have this now, and not 1000miles earlier? Or why the others don't have this? (all pre-facelift, more or less the same mileage)

Mathieu_AMG

And a quick picture of the beast ;-)

jrcart

Beautiful ride, I love the wagon/estate but they do not sell them here in the states. We can get the E63 Estate here no however.

Good luck with a diagnosis and keep us posted. Check your oil level frequently, these motors consume oil big time due to the crankcase ventilation issues. I suppose you could be having a head gasket issue due to some expansion under extreme heat conditions and thus getting some weaping through there but I would still bet my dollar it's simply crank case blowby, I had similar issues with my 2008 CLK BS at track events, some smoke on throttle, no CEL's, no loss in performance....just really wet airboxes.

Mathieu_AMG

Checked the airboxes today, as dry as they can be...

Went for a spirited drive, high speed, high rpm's, no problems, no smoke.

Went home, low speed, low rpm's and a lot of traffic. A CEL came up on my dashboard.

Going to the dealer next week, hope they find something!

Merc63

Smoke out the tail pipes or smoke out the car from where ever?

You have a problem for sure. I've tracked before and never had smoke.

Something is probably leaking hitting the hot engine under the temps and pressure from track use.

Merc63

And doesn't a c63 over steer?? Never heard of one under steering before..

Mathieu_AMG

Smoke was coming out of the tail pipes, and quite a lot of it... But only in short clouds, not constantly.

If you go hard on the throttle it will oversteer for sure, but if you try to build up corner speed and go gentle on the throttle, the front will go wide, a long time before the rear starts to move. On a public road, you'll never notice this, only when you start pushing it on track.

I really have to go slow into the corner, get my front wheels back straight and go on the throttle. I did a few laps with a friend's GT3, corner entry speeds are just crazy :-)

But this has a lot to do with the tires. In front I have some cheap tires (from the previous owner) in the back I have new Michelin Pilot SuperSports, so that's a recipe for understeer!

As for alignment;

front 2,1° negative camber, toe in factory spec.
back; 1,5° negative camber, 0,09° toe in

H&R lowering springs, performance package suspension
H&R 15mm spacers in front, 10mm spacers in the back

I have never felt a difference with the spacers, but it looks nice ;-)

Merc63

Id go hard into corners and the back would only move, obviously you have some crap tires on the front causing this.

What was the code?

K-Mac

K-MAC manufacture precisely adjustable (single wrench) front Camber and Caster and rear Camber (with extra Toe) adjuster kits.

Track days can wind on another 2 degrees of negative Camber up front to go deeper into the corners with reduced under steer. With the positive Caster adjustment capability also reducing dive/lift under brake and acceleration.

wampire

If you have a long and fast corner same is happening to me front is going out on a short corner its easy to oversteer and im runing Nitto tires. Stll have to do weight balance of a car and then check again.

Mathieu_AMG

Same here, short corners, go hard on the throttle and oversteer (looks cool but is the slow way)

Fast corners, understeer starts to build up. If you go on the throttle, you are just pushing the car over the front wheels.

I didn't do a weight balance, but I put it on a scale once and the front axle has about 50kg more weight than the rear. Not that bad for a 1800kg car...

I must say, I am running the car in "sport handling mode". Not with the traction control completely off. But I don't think that the traction control is interfering at the moment the car understeers.

wampire

Yeap me the same Sport Mode on for limited slip. Still didnt take it on a track after i put KW. Will see how much KW will help

olszowa12

Very nice estate

Mathieu_AMG

Ok, small update;

I got the car back today from the dealer. They were able to replicate the blue smoke problem; leave the car on idle for a time, wait, give it some throttle and it starts to smoke.

I didn't get a chance to talk to the mechanic, it's what the salesman told me. They are sending their findings to the national dealer of Mercedes Belgium in Brussels and look what they say. If they say it's normal and it's still in tolerance of what mercedes considers normal oil use, the car is fine. If they say it's not normal, they will change whatever is necessary.

Still not very happy with the "solution". At the moment this is not such a big issue, under normal conditions, the car doesn't smoke. But I'm pretty sure this will not get better in time, only worse...

Another thing they noticed; at cold start, when you put the car in drive, it takes a while for the torque convertor to cut in, and you start pretty aggressive. If you drive a minute and take off again, it's as smooth as it can be. Only happens at cold start, after the car is standing still for a few hours.

bhamg

Since you're so close to the expiration of your warranty push hard for them to do SOMETHING. You don't mention the mileage on the car or the current rate of oil consumption but don't forget that excessive oil consumption is a catalytic converter killer. Carbon buildup inside the cats closes down the pore size in the honeycomb, resulting in reduced efficiency (think premature replacement $$$$) and less power due to restricted gas flow. Your condition is abnormal regardless of oil consumption.

Critter

PCV< is malfunctioning

AMGangster

My car does the same thing each time I got for an open lap day. The first run I go out the car smokes, I get black flagged, and worry. I go in the pits and after it cools I go back out and it runs perfectly fine. My thought is the car is cleaning out the build up of from daily driving. I've done this 2-3 times this year exactly the same way.

Critter

Time for a catch can,

andya34

what was the out come?

Razzy

Clearly you diagnosed your own "understeering" problem. Your front tires are **** and that needs to be looked after. You can the best car on the best suspension etc but if your tires are garbage it is all futile.

The C63 is not understeer bias, more like oversteer bias and has that rotational ability that many cars don't have just by touching the throttle.

Perhaps you should read a few reviews and get some practice. You running too hot into a corner and running wide is not called understeer.

PS: Turn the TC/ESP off. Jesus, no wonder that is exasperating your so called front end problem. Contrary to what you are saying about the electronics not interfering in sport mode, I am not buying that. I've had the car in sport mode on the street and it interferes, can't imagine how much it would on the track.

andya34

what was the out come?