2004 Brake Drag
 

I've been researching the boards looking for info about a problem I'm having with my 2004 E320 Tourer. Recently it has felt like the brakes are engaged and the car slows to a stop when I lift my foot off of the gas. I thought it might be the SBC since I've noticed some similar complaints on the 500SL board. I've even noted the problem mentioned in the following British review:

http://www.topgear.com/servlet/tg?DE...Number=20.html

But the one thing I can't seem to find is an explanation for the dealer (who mysteriously doesn't feel it at all!).

Any thought would be greatly appreciated.

Dave In Charleston
2004 E320
1986 560SL

Hi,
I have had my E320 now for six months.
Just let me lell you that here in England my car came with SBC and also SBH.
Ok SBC lets the driver after comimg to a complete stop, depress the footbrake pedal firmly and the car holds the brakes untill either the gas pedal or the footbrake pedal is applied again (handy for holding the car on steep hills.)

SBH..Which seems to me the problem that you are experiancing.
I don,t think that SBH is fitted into the U.S. cars

But here goes I don,t know if I,ve got it wrong way round SBC or SBH one of the other anyway the light below the speedomter lights up telling you anyway.

The other one of the two which I guess is your problem.
I can have the car automaticaly brake at low speeds not sure but about 20 M.P.H. downwards (this is andy when in slow moving traffic) when you take your foot off the gas pedal the brakes will go on automaticaly and can feel the brakes bind.
this feature is set by holding down the cruise control arm when the car is stood and can be disengaged buy moving the cruise control again.

This gimick is ok but takes a little getting used to opperate it.

So my guess is that the sbc or sbh computer wants a reset or some part was installed or uninstalled when the car was manufactured.

I hope this helps

leslierushforth@aol.com

Chesterfield England.

I know what you are feeling and I think its just one of the idiosyncracies of the car. I think I read somewhere that if you rapidly remove your foot from the gas the system "prepares" to brake. That is the only scenario that made any sense to me. I have to say that the brakes have been the weak link on this car for me but otherwise has been quite fabulous.

Thanks for the reply 04E500,

I thought that it might be an idiosyncrasy of the new SBC system, but my wife and I swear that it has gotten worse over the last few weeks. It's starting to feel like a caliper is always tight. You have to really step on the gas to get the car moving and if you release the accelerator, the car comes to a stop.

I love this car, but my driving enjoyment has been diminished due to the stress of the braking system. Unless I have an error code, the dealership wants me to stay away.

Dave

:) Well let me just say this (car built July 2003).
The brakes on mine work great I have NO problems whats so ever.
I would be dead driving another car other than w211.
A guy pulled accross me on the freeway doing 80M.P.H.
I hit the brakes and took avasive action on the steeering
The on board computer took over the problem, thank god or I would be dead.
I was able take full control without spining the car.

Charleston, you can figure out if one of the calipers is applying pressure when it ought not, but you need a thermometer. Just find a 1/2-3/4 mile stretch of road, take off from a start, do not apply the brakes other than to stop at the other end and then check the temp of the brake rotors. I would probably try this experiment 6-10 times to eliminate the brake force distribution issue. If one of the rotors is consistently higher than the other you would have a legitimate complaint.

You probably need an infrared or contact thermometer to get accurate reading. PITA but for the peace of mind might be worth it.

Stay away? Speak to the service manager and demand that you want your car checked for ALL software upgrades & service bulletins - engine, audio/gateway, etc. I said this before, and I'll say it again DO NOT take for granted that software upgrades (even dating back to "03) have been applied simply because of your build date or model year. And by no means take for granted that the dealer has checked before delivering the car to you. And lastly, don't take for granted that the service dept. automatically checks when you have the car in for service.

Excellent idea Konigsteiger.

I'm going to call my service tech to see if the software is current.

I should have mentioned when writing this thread that I also had a problem with the tire pressure monitor. It gave a reset warning that required the dealer and after examination, they found a mysterious liquid in the tire. At first they wanted to know if I had used fix-a-flat (I hadn't). I'm not sure if the two are elated, but it does seem like the car was hesitating and slowing down around the same time.

Dave

_______________________

Liquid in the tire by no reason? (sounds like X files to me)

The only time I had liquid in my tire was after using the Fix-a-flat type of foam during a small puncture. When they changed the tire the water (about half a cup) came out of the tire.

Is there a possibility that the car may have had a puncture or gone through a pot-hole just barely damaging the tire (or brake parts for that matter) before you got your car?.

Did the shop check anything else apart from the tire.

Not trying to worry you, but just a though.

One possibility for what you are experiencing is actually engine braking. The transmissions on these cars have torque converters with lock up cluches in all forward gears. Depending on your speed and which gear you were in, when you lift off the accelerator pedal you could be sensing the engine as a braking force.

I reread this post and laughed. Good intentions of course but the other guys are right. Take it back to the dealer and have it handled by the "professionals" under your warranty.

Konig is correct, you cannot assume anything. I had the drifting to the right problem that required the bolt kit update and I purchased an 04' 6 weeks ago.

I have to disagree with this statement from my personal expieriences. The braking system on my car is one of the best Ive ever owned. Very smooth and pleanty of braking power under foot....

I will however agree with the torque converter lock up theory.... I too feel this when I let up on the gas at very low speeds, but have excepted this as the norm and does not bother me at all.....

The brakes are near impossible to modulate coming to a stop and it drives me crazy, I have all but given up and am simply getting used to the car lurching slightly when stopping. The brakes definetly stop the car and do so well for the size/weight of the car. Maybe your driving habits are different but my opinion is that this unwanted electronic intervention is a glaring wart on an otherwise spectacular car.

I've read and expierienced this complaint, but it seemed to be on just the 03's.... I've not heard complaints about the 04's brakes being "touchy" as yours is the first. I originaly test drove the 03 and also had expierienced the "lurchy" feeling, but didn't seem to bother me too much and figured it would be something to get used to as time went by. I ended up ordering an 04 because I wanted the active headlights and the 7G tranny... From what I understand and have read here in this forum, they have improved the system with an upgrade called "soft stop" on the 04s... Perhaps your car does not have this upgrade and it is something that can be done at the dealer.... What is the build date of your 04???? Again, my brakes are silky smooth and yes I do feel a difference between my car (an 04) and the 03 I originaly test drove.....

Yes, I think this is what it is. The e class tranmission likes to keep a low gear and when you let go of the gas and coast it will downshift (that is go to a lower gear 4->3 for example) which causes the engine braking effect. I do not think it is the engines dragging... my e does this too, it is normal

I went out and drove my E in a few different conditions today after reading a few of the new threads concerning the engine downshifting. I have to agree that it DOES seem to be the tranny and not the brakes. When I shift to neutral, the car glides freely. When the transmission is set to S it seems to become more touch in slow speed conditions. We felt that the "C" setting relieved this.

Unless I'm nuts, I could swear that the car was smoother a month ago. It's a 11/03 build car, so I'm unsure if there has been an update to the software that might smooth things out.

I don't know the build date but i would agree that my 04 is better than the 03, yet I still cannot soft stop the car as you put it. Maybe I should check into a software update.

There are obviously variations from one car to the next regarding the behavior of the brakes. I had a pre-nav "03 and now a replacement '03 w/nav. (FYI - softstop is also on the '03's). Both vehicles stop smoothly, the breaking is linear and I find breaking reaction to my pedal input to be as or more controllable than traditional sytems. As a matter of fact I had to ask my dealer if my first car actually had the electro-hydraullic system as it didn't feel any different. Yet others have posted different experiences as have many auto reviews which usually have found the brakes to be one of the biggest flaws in this vehicle.

After reading multiple comments in auto magazines and posts on this site and others I'm convinced that this new break system is intuitive for some and not for others. I find this to be the weak link in my car and it decreases the driving pleasure tremedously. Is it a right/left brain thing? I know that others who have driven my car think I'm nuts when I tell them I can't stand the breaks. I've complained to the dealer but they assure me that it's normal. I'm told there are no software updates. Sounds like there may be an objective difference in the 04' but I still run into complaints on the boards.

Can someone with on '04 try something for me? I'm convinced that the hesitation I'm experiencing is not related to the brakes. I was pulling out of my parking spot yesterday and it felt like I left the parking brake on again (it wasn't). I pulled up to the light and took my foot off the gas and the car did not move. It was like I still had the brake depressed. Can some else try this too? I'd like to hear if this is something unique to my car since I don't seem to have noticed this "drag" before.

Dave

Don’t know the build date of your vehicle but as I mentioned before this actually doesn’t matter. You say your dealer claims that no updates are available for the problem as YOU describe it to him as being the brakes. Star bulletin P-B-07.00/28e (engine control unit software update) is a starting point with your dealer’s service department. I think what you’re experiencing is the ECU not the brakes because this bulletin corrects (1) Lack of power and (2) Hesitation caused by “two-footed” driver (i.e.: driver depresses accelerator & brake pedal at the same time). A shot in the dark, but I think you may be experiencing an “as if” two-footed hesitation being caused by the ECU. Bring it in, suggest the bulletin and ask that the service manager road test with you.

As far as the engine braking that e500 and matt5555 mentioned, I generally enjoy it as it feels more like a manual transmission car. But when driving in the mountains, I sometimes didn't want as much engine braking. I found that if I pushed the gear selector to "+" eventhough the car was already in "D" that the transmission would shift to a higher gear. Anybody else notice this?

Good luck with your brakes CharlestonBenz. My car felt like one of the calipers would grab before the others when I applied the brakes. My complaint was basically ignored the first time. On a return visit, I asked to drive another car. I noticed a big difference between the 2 cars. I had the service advisor compare my car to the other car, and my complaint "I think" became more real to him. I treat the advisor with respect; I do not become angry, but I am persistent. The calipers and pads were disassembled, and re-assembled and the issue was solved. Moral(s) - (1)be persistent, (2)ask for another car for comparison

William in Miami, FL
2003 E 320

I tend to notice this condition (torque coverter lock-up) more when the engine is cold, but seems its always present to some degree... It's just not as evedent when the car is warmed up.... Although I've never experienced this in an automatic trans and agree with an earlier post that it feels like a manual sometimes, this doen't seem to bother me.....

I notice that whith my clk also. When the car is in D I can upshift and it does. I dont know why though.

Update
 

Heres an update to my brake problem.

I took the car into the dealership this morning to address the drag I have been feeling. Like some have recommended on this thread, he and I drove a new '04 E320 and then drove mine. After 4 trips, he finally admitted that he felt the drag too.

The technician took it for a spin and felt that the intelligent engine system needed to be reset. My car is upshifting early he noted. He also said that there is a problem with the torque converter and that MB is aware of this and is working on a software upgrade.

I should notice an improvement in a few days as the car "learns" my driving habits again.

Dave