Hello all, I just joined this forum and this is my first post. My name is Nick and I own a 2011 (first new car!!) C300 (w204) sport. I bought it about 6 months ago and has about 5400 miles on it and it is starting to act up..... I'm not sure if I am being over **** or if my car actually has problems. As a side note (not sure if this matters) but I was in an accident in the first month with 1000 miles on it because I fell asleep "I was working 20 hours straight, please dont give me crap" and was going about 40 and hit a curb on a turn and scratched the rim and broke the shock and and wishbone. It was so stupid but i'm just happy to be alive. I fixed everything that was wrong and got oem and it drives straight and fine. But now I feel like my car is falling apart. I don't know if i'm just nit-picking after my "incident" or if my car is really falling apart.

So my problems:

Well like the title of this post, right now I was driving my car and when I was slowing down when it gets below 20 to a stop the car jerk strongly. Feels like i am pushing the break down then letting off. I've been reading and not sure I should reset my tcu or if my transmission is going out. It was really bugging me today and its uncomfortable....

Another issue I'm having is my sunroof, ok I know things begin to squeek and make sounds but not on a car with 5k miles. Whenever I tilt the sunroof it makes a weird stuttering sound? Its like a farting sound haha. I dont know how to explain it. It sounds like it is not lubricated and the rubber is rubbing against something and the sunroof is struggling to go up. I use it a lot since its been hot. But its very loud and just doesn't sound healthy.

Last issue is that there is a cracking/ popping sound when ever I drive down a driveway or make a turn on a sleep slope. This is annoying/ I've been reading about a lot of people having this issue but I don't really think its anything serious....


Well I appreciate any help guys. Definatley do not have to answer all or any of my questions. Thanks you and please also do tell me if im being over the top and need to get a life =) or if I should get things fixed..... Also I'm not sure if Mercedes would void my warranty since did get in a accident but I did get it all replaced and did it cash not through insurance so I don't think anything was recorded. I also want to note there is a small crinkle/ dent near the sun roof on the side which I had my accident. Really not noticeable (I saw it because I am ****) but its about the size of a thumb and I think it was from the accident (body of the car flexing/ bending) but no frame damage. Maybe ill make something up???
But thanks everyone sorry for it being so long but it's all been bugging me. I will upload a pic of the damage and the roof if you guys want. and tell me how

 

The jerking (and I assume that you mean the steering wheel) is likely caused by the brake on the wheel that was damaged. Take a look at the wheel speed sensor on that side.

The sunroof stuttering I am quite familiar with although mine does it only when the roof is hot. My dealer did some lubricating but it's back. This is warranty.

The cracking/popping is very well known and it's cause by a bushing (s) which will be repaired under warranty. Mine have been replaced twice.

The wrinkle in the roof is something else again. Did you really do the repairs yourself? Bad idea since some supporting structure may have been damaged.

Properly repaired collision damage has no effect on your warranty but when trade-in or lease return comes around, this will be spotted and you may have a problem

 

Umm no I didnt do the repairs myself. I took it to a certified mercedes collision center but I know a guy. I paid it all cash he did all the work I didnt. umm... No the steering wheel does not jerk. the transmission jerks. As in when I break the transmission shifts to 2nd or 1st gear when I get below 20mph and it feels like someone is downshifting but its only when slowing down.

The frame was checked and i actually replaced more than necessary he said. A lot wasnt even damaged in the wheel well but I had him replace a lot of it because I didnt want problems. He ordered all the parts from MB so i assume they are OEM.

It is the transmission doing the jerking. The brakes are fine they stop straight and they are ok.

 

I had a transmission jerk issue on downshifts. No joke, it felt as if I was being rear-ended every other time I slowed down. Took it to the dealer and after a very unpleasant experience with S.A. PATTY KIM @ BENZEL-BUSCH ENGLEWOOD, NJ that is detailed in another thread, I got it fixed via a "transmission diagnosis and re-flash". (I will note that I had the WORST dealer experience ever with Benzel-Busch and Patty Kim and it is detailed in another thread I started... Long story short, needed my car back that day and SA left work without calling me to get my car. I had asked them to perform service B + transmission flush + front brakes and to call back with an opinion on why my transmission was jerking so hard on downshifts BEFORE performing a transmission diagnosis [$300+ dollars for pressing a few buttons on a handheld computer??] so that I could make an educated decision on whether or not to spend so much damn $$$ [imagine if it were a hardware issue and the software reflash did NOTHING!].

I will note this has happened in every mercedes I've driven (03 E320, 06 ML500, 09 C300 sport) @ approximately 50,000 miles. I attribute it to my feather footed driving, I rarely let the rpm above 2500-3000 and love to coast without braking to a stop.

It hasn't happened yet in our 2010 E350 Coupe but that car only has 23,000 miles and is driven with a lead foot (not me).

Other members (maybe RLE?) have commented that rough UPSHIFTS can indicate a malfunctioning electro-hydraulic valve in the transmission. They also noted that the failed electro-hydraulic valve is a KNOWN issue with the 922.1(?) [correct me if I'm wrong] transmission in our c class.

 

Hmmm..... Yeah I drive rush hour every day so I can see why it learned a odd driving style......Ummmm instead of taking it to the dealer can I just reset the TCU myself. Because I really dont want to deal with it and the dealer.... I've seen forums on people reflashing it themselves... does that work the same

 

When I was in LI I used to sit on the 495 to Manhattan every day. The constant stop and go would confuse the transmission periodically... I don't know what kind of parameters the adaptive transmission works with but if that could cause the symptoms described I feel like we shouldn't have to shell out big bucks to have them "diagnose" the problem if it's something that could potentially happen to all of them. But that's business I guess...

I was unlucky because they both flushed and "diagnosed"/re-flashed my transmission on the same visit (I had asked my SA to call me before performing the latter, which she didn't, so I would know the results of the "extensive" inspections on the B service as well as the ATF condition. Who knows if I even needed that $300 a la carte item... )

The OP's car is only a few thousand miles old so I guess the ATF woudl be a non issue.

There is a way to reset the throttle position sensor by turning the ignition and pressing the gas pedal in a certain pattern... i'll look for it.

But resetting the transmission to re-learn might need one of those handheld computers. My guess is that you're better off doing that at an independent shop because the dealer will rape you on it

 

The transmission issue should be solved in a Transmission Flash though odd Mercedes didn't do a Firmware upgrade on the 2011 guess it depends on Manufacture date.

Sunroof yes totally annoying sound but lub it up and good to go dealer will do underwarranty. No idea how that passed quality control....

 

Ask the dealer to fill you in on lubing the sunroof yourself. You will then be in a good position to maintain it out of warranty free of any cost .!

 

Hmmm..... I don't the accident is what has caused your car these problems. well maybe the dent in the roof. But I have heard of the sunroofs on the C's making weird noises especially when it is really hot. Or Cold. Mine makes noises sometimes but too lazy to take it in...

I am actually having the same problem with the clicking/ popping noise. I also have read that people have been having problems with that. I think you should take it into the dealer. I dont think warranty will be affected because you could just said you hit a curb. Dont tell them how and just say it was in a parking lot lol. You can say you have no idea how it happened and maybe a valet guy did it....

But i think the transmission should be reset in my opinion. You can do it yourself and there is step by stem guide on another post (ill try to find it for you). But everything else should be covered by warranty. Because if you think about it the cars are made to withstand these things. When they test them I know that they drive them to the ends of the earth in order to pretty much see if they can break/wear down everything, including the suspension. I think what you are experience car wise are little niggles, but I think your being a bit too nit-picky. I'm pretty sure you didnt do anything to your car, I mean i know people who hit trees at 40mph and they get their cars fixed so i mean hey what you did is minor, and i think take it in to the dealer under warranty and maybe reset the trans yourself... Agree anyone???

Oh and on a side not does anyone know if reseting the trans. voids the warranty on the car..... or at least the transmission because i want to but im not sure if it does?

 

12 years after the fact I'm sure the OP has found his solution by now.

 

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