Any armchair technicians?
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Any armchair technicians?
Mercedes has had our 2014 E250 for a total of about two weeks now between two separate sessions trying to chase down a noise.
When you first pull away from a stop, there is a quiet hollow sounding "bonk" that happens.
The dealership has replaced suspension components, the driveshaft, and when that didn't fix it, has checked other suspension components and the brakes. They've been speaking with techs at MB Canada HQ for direction, and even sent them a sample of the noise, but they still don't have it nailed down.
I admire their resolve as I suspect other brands may have given up by now, but this is going on a little too long.
Has anyone experienced anything similar and have any ideas?
When you first pull away from a stop, there is a quiet hollow sounding "bonk" that happens.
The dealership has replaced suspension components, the driveshaft, and when that didn't fix it, has checked other suspension components and the brakes. They've been speaking with techs at MB Canada HQ for direction, and even sent them a sample of the noise, but they still don't have it nailed down.
I admire their resolve as I suspect other brands may have given up by now, but this is going on a little too long.
Has anyone experienced anything similar and have any ideas?
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From: NJ
E300-4matic
I Would be surprised to hear your problem is suspension related. You are saying that as soon as you add power you hear a sound that to my ears (of course never having heard it) is akin to a thumping sound, I would guess (as that's all anyone can offer) your problem has something to do with either the fuel delivery system or perhaps the air intake. The reason I mention these two items is that it is unlikely your car's suspension would make the type of noise yo describe and than stop once you add power, but the biggest change your car goes thru from a standing stop is that you are adding power,hence the fuel and the air that makes the car move forward is the addition of the fuel & air.
Firstly, did your dealer check to make sure the air filter housing is securely attached to the rubber grommet to the intake manifold, and that there is nothing blocking the air filters in the air filter housing. I Am assuming that your dealer checked for trouble codes using his OBD and also you have no "check engine " light that's lit up. Finally, I assume you have a gas engine and you've been putting high test gasoline in your car, if you try to cut corners by putting mid grade fuel in your cr that will over the course of time really screw up your engine and any damage from doing that will not be covered by your MB warranty, I've seen this exact situation happen with a customer at my local MB dealer on a leased vehicle. If I was having the problem you are describing I would ask the dealer to check for "trouble codes " and replace the fuel filter, the air filters and lastly check the O2 sensors. Best of luck.
1guitar
Firstly, did your dealer check to make sure the air filter housing is securely attached to the rubber grommet to the intake manifold, and that there is nothing blocking the air filters in the air filter housing. I Am assuming that your dealer checked for trouble codes using his OBD and also you have no "check engine " light that's lit up. Finally, I assume you have a gas engine and you've been putting high test gasoline in your car, if you try to cut corners by putting mid grade fuel in your cr that will over the course of time really screw up your engine and any damage from doing that will not be covered by your MB warranty, I've seen this exact situation happen with a customer at my local MB dealer on a leased vehicle. If I was having the problem you are describing I would ask the dealer to check for "trouble codes " and replace the fuel filter, the air filters and lastly check the O2 sensors. Best of luck.
1guitar
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2011 E63, 2011 Hyundai Genesis 4.6 v8, 2013 GMC Denali XL, 1965 Ford Mustang, 2005 Merc. E500
Motor mounts? transmission mount? Center Driveshaft bearing and mount? Exhaust system mount?
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It's a diesel, so poor octane isn't the problem. 
The noise appears to come from behind the driver's seat, so, I would guess it isn't engine related. U
Exhaust mounts could be an issue, and maybe engine mounts if the vibration somehow get transferred through the chassis. They've replaced the DS and mounts, and it didn't help... I can only assume they've checked codes, that's usually the first step, isn't it?
It will be interesting to see what the trouble was when this is finally found.
The noise appears to come from behind the driver's seat, so, I would guess it isn't engine related. U
Exhaust mounts could be an issue, and maybe engine mounts if the vibration somehow get transferred through the chassis. They've replaced the DS and mounts, and it didn't help... I can only assume they've checked codes, that's usually the first step, isn't it?
It will be interesting to see what the trouble was when this is finally found.
Last edited by looney100; Mar 7, 2015 at 06:49 PM.
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From: Athens, GA USA
2011 E63, 2011 Hyundai Genesis 4.6 v8, 2013 GMC Denali XL, 1965 Ford Mustang, 2005 Merc. E500
Behind drivers seat comment makes me think it is still driveshaft related. Were both sections of driveshaft replaced along with center bearing and center driveshaft mount replaced, and were the two flex disc replaced with new ones?
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Presently 19 S560 SEDAN, 2014 XK, SOLD GLE 450e
I've had that symptom on another make of car. You take off from a stop light and here 'thunk' when you do that. On that car it was one of the three differential mounts gone bad. It was the 'front' mount on the differential. the one near where the driveshaft connects to the differential.
When you take off from a stop light the front end of the differential wants to rotate upwards and that front mount prevents the front of the differential from rising up and hittng the floor above.
On That make of car the mounts rubber had sheared intwo. When You looked causally at it, it seemed to be whole. But when you put it in gear and moved fwd, you could see the rubber was sheared and letting the front of the differential rise up and hit the floor.
I've never looked under a E class so it may be made differntly than the car I had the problem on.
When you take off from a stop light the front end of the differential wants to rotate upwards and that front mount prevents the front of the differential from rising up and hittng the floor above.
On That make of car the mounts rubber had sheared intwo. When You looked causally at it, it seemed to be whole. But when you put it in gear and moved fwd, you could see the rubber was sheared and letting the front of the differential rise up and hit the floor.
I've never looked under a E class so it may be made differntly than the car I had the problem on.
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MY17 E43 Matte Selenite/Macchiato Beige, MY16 GLE350d Tenorite/Crystal Grey, MY17 B250
Really long shot, but I had an ML550 that made a strange tap noise frequently when accelerating from a stop. I eventually narrowed it down to the passenger seat area where I found an "extra" seat bolt down in the subframe that was rattling around down there. I guess when they installed the seat, they dropped the bolt and didn't bother to fish it out.
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From: NJ
E300-4matic
Lemon Law?
Most States in the USA have "Lemon Laws", my state's lemon law says that if you've taken your car back to the dealer at least 3 times for the same problem and the car is still under its' original warranty the fourth time they either have to fix it for good or replace the car, simple as that and I know it has happened for real at my dealer, the car in question was an 2007, S600 but MB bit the bullet and replaced it. It didn't hurt that MB headquarters for North America was also located in NJ where the incident occurred. FYI, MB is moving its North American headquarters to Georgia this year, there is a reason that MB and many other car manufacturers are moving to places like Georgia, South Carolina, Kentucky, etc., those states are very business friendly and don't have things like "Lemon Laws" plus their tax structures for business are very friendly, so much for the consumer. Good luck to you, it might not hurt to write a few letters to MB headquarters in Montvale, NJ, that way when you get really fed up you can tell MB either replace the car or get ready to go to court, that will get their ears wide open. After all, when you pay $50k+ for a car expecting it to run reliably isn't an unreasonable expectation.
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The diff has proven fruitless. They're now onto the transmission. I kind of wish I was in the US where the lemon laws exist. I'm not sure what the end game is here if they can't find it and/or give up.
As long as they fix it, I'm not too fussed. I've got to make due with a C300 in the meantime that isn't as fuel efficient as the E250, but I'm racking up mileage in someone else's car.
As long as they fix it, I'm not too fussed. I've got to make due with a C300 in the meantime that isn't as fuel efficient as the E250, but I'm racking up mileage in someone else's car.
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I picked up the car today. They've ordered a new transmission, and need to wait for it to arrive from Deutchland, so we're driving the car again for a couple weeks.
I hope this will solve the problem. This repair will cost them a mint by the time it is finished.
I hope this will solve the problem. This repair will cost them a mint by the time it is finished.
