djsb

My coupe has been extremely instable. Now, when it rains if the road has some watter, it starts aquaplaning often and its getting quite dangerous driving this car.

I had tried different brands of tyres like yokohama, goodyear f1, michelin pilotsport, continental sporcontact2, ...

All tyres do the same. My tyre dimensions are 225r17. I think they are not so big that can produce this results. I have also an audi A4 with 245 tyres and it does not do the same.

Also the car is unstable in bumpy roads.. I had the car to mercedes workshop and they replaced the ESP and central processing unit but it keeps the same.

Any ideas?

amdeutsch

Slow down.

djsb

I wish. Even if i get extremely slow and all other cars pass trought mine with twice of my actual speed i keep getting instable driving.

Today, i was about 70km/h on the highway and i got all kind of cars passing through mine (they were at about 120km/h).

amdeutsch

OK, but have you not learned anything between now and your first post on this forum, about a year ago, where you described having similar problems? Afterall you have had a year of more driving experience. Or do you live in that part of the world where rain is rare and therefore in the spring, rainy season, you have control issues.

Chi500

did you make sure that the tires are inflated to the recommended pressures? if not that maybe your problem.

advans

get Radials, all seasons or snow tires lol check out the tire's "water" performance rating before u buy it! or maybe do u have ur ESP on or off

Outland

This is a crap thread. The C - Class, and obviously the Coupes, are extremely stable at speed, regardless of the weather.

Are your tires bald?
Are they loosing air pressure over time?
Is the suspension damaged?
Are the wheels true?

Don't give us 'my a4 was blah blah blah' crap. Your car is either damaged in some way, defective, or you can't drive.

MHPHOCKEY

you are my hero outland...haha...i agree, learn to drive

Moviela

My suggestion would be to get some taxi coupons for rainy days.

Seriously, you should come to the US and attend a competition driving school with wet skid pad training. It will improve your skills for road driving, and unlearn all the bad habits you have picked up.

My friend took a class and discovered the problem with his Porsche was the nut loose behind the wheel.

djsb

No. My previous post about a year ago was about unstable driving in bumpy roads. I went to a mercedes workshop and they changed the esp module (that had some wrong values when activated) and they also changed the central processing unit (it was an expensive repair) but it keeps all the same. The car keeps unstable but now it can go through high declivity ramps.

Now it started the rain period. It has rainned alot since since last year and just now i'm having this aquaplaning sensation.

Mercedes mechanics said the car had never had an accident or the chassis is in good shape. I don't know what to do..

Thank you for your reply.

djsb

Of couse i agree with you it must be defective. I have a friend who has a coupe and it is exttremely stable even on wet road. My car is also very stable at speed and while turning directions on high speed. The problem is only that when i have a bumpy high way or a wet road it's really insecure. I guess it's not my driving as mercedes mechanics feel the same, but can't fix it.

My tyres are ok. I've tried different types of brands. The pressure is ok. I've tried also differente pressures on each tyre. The suspension is like new (at least it's what they said on mercedes workshop) and the wheels are original 17" mercedes benz wheels.

djsb

Everyone to whom i describe the problem say that... Unhappyly they change their mind after they drive it on that conditions...

Outland

Tires and shocks are the only two things that come to mind...and BTW, you really shouldn't be driving fast on a bumpy road in the wet, regardless of the kind of car.

advans

My car is great in rain! even with ultra high performance tires! maybe you should learn to drive the coupe

MHPHOCKEY

I did Skip Barber at Laguna Seca...absolutely unreal. Cannot begin to tell you how much it helped.

c230kracer

I get that problem too but seriously....i dont think its the tires anymore..as i did before i bought my sumitomo's. THey have great threading for going through water or whatever, but i still cant be driving fast in the rain....just wont happen...i tried going about 45-50mph...my car starts to sway right and left and i feel like my car is off the floor "hydroplaning" and the solution is to literally slow down...even though i feel like i my car shouldn't be doing what its doing when a lil Bucket car Hyundai or something flys by me going like 60 with no problem....i start thinking after that....haha other than slowing down, maybe getting new shocks and springs? well thats my input and self observations about this problem...dont worry i get it too! haha

rubensans

Then what will I have with 18' and 255??

Best Regards.

djsb

To all that say: "learn how to drive". Yes i could use some lessons about agressive driving. We all should have them.

When i drive a friends coupe evolution that is just like mine (wheels, shockabsorvers, etc) and it has nothing to do with mine. It's incredible stable. So it shouldn't be a driving problem...

About the speed. The car slides even at very slow speeds.

Moviela

I wonder if it is not time to have the factory brought into the loop. There is an incredible amount of sensors, processors, and mechanical parts that must work together to make the car stable. Most of it can be tested through the Star Diagnosis system. Some items cannot, and need he eye of an experienced engineer. It could be something as simple as a bad battery causing the "settings" to be lost whilst parked. It might be more complex, like a failure of the brakes to properly follow commands from the ESP because of air in the lines or dirty fluid.

Please ask the factory rep in your country to get involved, and assist the dealer in making your car safe.

djsb

Thank you for your quote. MB representative for my country is analysing the car and it's been a case of study.

sgb33f

not sure if this is possible...but how abt the diff? could a slight defect in the diff cause the rear tires to lose traction easier in the rain?

revstriker

If his car truly is hydroplaning, then it really has little to do with his driving ability other than his speed in wet weather. Controlling a car while hydro-planing is all about driving ability (and of course, ESP), but this has not been listed as an issue.

If the car is actually hydroplaning, then it most likely has to do with the tires. Tread, and tread life, condition of the tire, and tire pressure are easy to check. If these check out, and your tires are designed for wet weather, then my next step would be to check the alignment and suspension.