W203 rumbling

[nAN3992]

Hi there.

Im owning a w203 c220 cdi 110kw 150ks. 722.6 automatic gearbox. Car is fitted with DPF filter. Im having an issue with the car when accelerating. Start off is fine, when i hit from 2nd to 3rd gear and RPM drop from 2000 (2nd gear) to 1100( 3rd gear) and i hold the accelerator the car starts rumbling, vibrating. I cant point out directly from where the sound comes. Sometimes i believe its from the end, sometimes front right passenger side ( its left hand car ), There is no sound-problem at iddle when revving, when going down a hill. The sound is a combination of vibrations, rumbling, shaking. No squeaking. Its a deep tone. The sound is there only when the car shifts when accelerating and hits lower rpms on next gear, once the revs go above 1500-1600 its gone. When i drive in manual mode i keep it on 2000-2200 rpm, shift at 2500 and the sound doesnt come up. Does anyone have a clue what could be the problem?

Things ive replaced on the car
Front engine mounts - both
Transmission mount
Front sway bar end links
Front control arms - all 4
Outer tie rod both sides
Rear springs
Rear sway bar end links
Brakes are tight, there is no play on pads
The rear struts are shaggy but i believe they cant cause the noise? Will be taken care off.


I checked the hand brake cabble that is underneath the heatshield when exposed. It isnt rubbing against the driveshaft, the clip isnt broken:
All heatshields are tight, no rattling from them. The car was taken to a local exhaust shop and they fixed middle exhaust hanger-mount, was a bit lose. Rear muffler had rust rotting and its been taken care off. The sound is still there. Its driving me crazy. Does anyone have an idea what could it be? The sound only appears when accelerating from 2nd to 3rd to 4th on lower rpms. Mostly and loudest is on 3rd when accelerating on low rpms. The sound isnt there if u cruse by at 1000-1400 rpms, once u start accelerating its there. No sound when iddling, no sound when driving down a hill, no sound on ramps.. Im really clueless.

 

[Jobsworth]

Sounds like a torque converter fault to me, specifically with the lock up clutch

 

[Jobsworth]

Is it like driving over a cattle grid or rumble strip?

 

[nAN3992]

Thanks for the answer.

I dont know how to describe the sound, it has a deep tone. I can feel the vibration inside the car once it happens. Cant either point out where it comes from, front or rear. It deffinetly isnt under the seat. Its not there if i drive down hill at 1000-1800 rpm range, but if i accelerate slow on a straight road and shift up it appears till it gets rpms up, then it goes away again. If im crusing at 60-70kmh in 4th gear at lower rpm and keep it at lower range rpm sometimes i hear a vibrating noise every 4-5 seconds. Non of this happens if i change the transmission to manual mode and change gears myself. I keep it always at 1800-2200 rpm and switch up on 2500-2700. The gears change smooth, no noise when switching PRND or gears - automatic or manual mode. I also checked air hoses for a leak but couldnt find any. All of this started happening approx 3-4 years ago when my mehanic took the exhaust ( complete setup) off the car to straighten up something around the exhaust manifold. As soon as i took the car i could feel a sound like blowing in an empty container/bottle It wasnt that often but with time it got worse. I never gone back to the mechanic because some other reassons i dont trust him anymore. Ps. I dont smell any exhaust smell inside the cabin, guess thats a good way to point out a bad manifold gasket?


Ps. the sound goes more towards the rumble strip you asked. It has a really deep tone, something like a v8 droning.
Pps. Cant reproduce the sound on ramps either with the car on air and in gear. Esp hits in, i manage to get it up to 1500 but nothing, no sound.

 

[Jobsworth]

With Star diagnosis machine you can temporarily turn off the TC lock up clutch for a road test. If you can find someone with this machine you can eliminate the torque converter

 

[nAN3992]

Will be hard to find someone who owns private a star diagnosis here where i am at. The only one who has it, at least that i know, is the mb dealer. Ill try with them, to see if they are willing to try and inpsect it. I really dont believe the issue is with the transmission. Im more towards the differential-axles. Noticed a vibrating noise on rear wheels when coming out of a roundabout. The car is on ts850 195-65-15" tyres. They are older DOT. Tomorrow im fitting newer pirelli p7 cinturato 205-55-16" just to eliminate that factor aswell.

Thank you for the tip. This week ill take it to a new mechanic to inspect the transmission, even tho its been inspected before by various people. Im having this problem for a longer time, believe the trans would fall aparat after 2-3 years with this problem?

 

[Petrol Pete]

Hello and welcome to the forum. You have carried out a lot of work on the car but you do not mention if the transmission has been serviced recently .

 

[nAN3992]

Hi
The car had a problem with the transmission few years ago (5). The shift knob was broken, the car wouldnt change from PRND on the dashboard. It would go to safe mode or lock up on first gear. I towed it on a truck to mechanic. Transmission was taken out, replaced everything inside, Im not a mechanic so sorry if i write something incorrect. They changed the valvde body aswell because they couldnt get the filter out, had to brake it with pliers. Lol. New shift knob all the way where it connects to the tranny. The transmission connector was dry, no oil inside, but put new in anyways. Once the tranny was out torque converter was inspected aswell and everything was fine. Added new oil, gasket, filter. That repair was done at around 210-215tish k kilometers. The car now has around 270.000. Ill be doing a new oil change soon.

The problem im having started the day they took out the exhaust system out. Instantly i could hear the noise at certain rpm. It sounded like blowing into an empty tube. With time it got worse. Im getting a fuel consumption of 9.3l at 100km. I believe it has increased since that day. 100% city driving though. Can diesel injector nozzles cause this kind of problems, i havent checked them. There is no fuel/oil around them, its dry. I even took out the air filter to inspect the heat shield under, it doesnt rattle. Im really clueless and its frustrating considering that i changed 70% of the car and cant get rid of this problem.

Ps. The fuel consumption was mesured by filling up to full, driving 100 kilometers then filling up again. The dashobard shows a fuel consumption from 6 to 7.5l. Depending on what type of traffic i drive in. If its open with no traffic jams i get it to 5.7-6l. On cold with traffic it sits around 7.5-8l. Thats what the board says. I run around 550 kilometers with 44 liters of diesel.


Pps. I can drive the car normal in manual mode with RPMS at 1500+. The rpm needle goes smooth, doesnt vibrate or drop when accelerating-slowing down. When slowing down im changing to lower gear with little bit of mid gas and it shifts smooth, no noise or jumps from transmission.
Just when its in automatic mode/D it shifts as soon as it hits 1900/2000rpm. As well as in S and in C mode. Then the vibration/sound/shaking comes up. Once it catches up to 1400 goes away. I dont like the shifting range on this transmission either. Do all 722.6 shift in every mode this early? Specially when going up a hill, have to keep the rpms at 1800 to keep it in 2nd gear, if i floor it to 2000-2100 it will switch to 3rd and i drop power and lose speed. The road condition doesnt allow me to drive in 3rd at certain rpm where the car wouldnt struggle.

 

[Stratman]

What year is your car? It's rather unlikely this late on, but you're describing some of the symptoms of the dreaded Valeo radiator problem. Loads about it on the search engine of your choice.

 

[nAN3992]

What year is your car? It's rather unlikely this late on, but you're describing some of the symptoms of the dreaded Valeo radiator problem. Loads about it on the search engine of your choice.

Hey,

Car is 2005. The facelift model. Ill do a research on the radiator problem to see if there is anything in common. Can i identify the current radiator i have on by visual looking at it or it needs to be taken out?

Ps. I balanced new tyres today, will fit them later to eliminate the tyre problem - if there is any. Currently driving with winter tyres.

Pps. Im reading about the valeo radiator problem. My coolant level is same for years, never had to fill it up. The color is same. I never noticed any leak of fluids. I inspect the car weekly by myself.


While driving today (outside temperature was +16c) i noticed the car is quieter? It doesnt rumble on lower rpms like before. I can still provoke the effect by myself but its at least 50% less then yesterday ( temperature was 6celsius). Can this problem be related to the outside temperature? Ill keep an ear it will be hotter in the next few days.


Btw. Is tihs car equiped with a catalytic converter? When looking from the bonet side with open hood i can see under the air filter box i believe thats the dpf? Underneath the car its just a straight pipe with 1 flex pipe and rear muffler. It has emission standard euro 4. No black smoke or smoke at all comming from the exhaust tips. It doesnt burn oil. I change the oil every 13-15.000km and before changing i inspect the level. It doesnt consume any oil at all. I always use mb 229.31 approval oil 5w30 or 5w40 depending on the summer temperature.


@Stratman i see you have a w203 c200 cdi is there any chance you can picture the underneath of your car (exhaust) for comparison? Is your car euro4 or the pre facelift model?

 

[Stratman]

My car is pre facelift, sadly I fear the state of my back precludes me from crawling under it to take a picture
I'll see what just holding the camera underneath and hoping provides.

I think MB had sorted the Valeo problem sometime in 2004, so yours should be ok, but worth searching. There is a published list of affected VINs which is quite easy to find.

 

[nAN3992]

My car is pre facelift, sadly I fear the state of my back precludes me from crawling under it to take a picture
I'll see what just holding the camera underneath and hoping provides.

I think MB had sorted the Valeo problem sometime in 2004, so yours should be ok, but worth searching. There is a published list of affected VINs which is quite easy to find.

Its ok, dont bother! I researched and found out i do not have the valeo radiator, luckly. At least one trouble to bypass me with this car. The situation is better with 16" new tyres. No vibration from the rear tyres anymore. The rumble went back tonight after the temperature dropped. Are there any rubber mounts that hold the rear differential axles or the differential? Any sort that could have play? Ill check tomorrow driveshaft for play and flex disc. The rear shocks are def on its way to the scrapyard. Dont think they could cause this problem, but in this state im not sure in anything..

 

[Stratman]

Phew!

The differential and rear subframe have rubber bushes, as does the propshaft centre bearing mount. All have been known to go soggy.

 

[nAN3992]

Thank you @Stratman !
I didnt inspect them. Will take a look at them tomorrow morning asap.

 

[nAN3992]

Ok so i inspected the whole rear end. Everything is fine, no play. When inspecting the shaft, at the end, when i place my hand on it and turn it clockwise, counter clockwise i can feel a small "click" sound. Is that normal? Besides that i couldnt find anything else. The bolts are tightened by spec. And man with the temperature increase the car feels better, spec the rear end where i have shaggy shocks. First i have to buy a good, strong, heavy duty, floor jack. Was using a scissor jack with no problems, securing the car with wood blocks. Then bought a bottle jack, man was i dumb. I placed it under the side jacking point right in the middle. I didnt know the jacking point was there being secured by a plastic bolt. The jack went straight through the bolt and inside the car. Luckly no structure damage, placed a new pad in. After that i bought a cheap trolley jack. Shit said it was 2 ton rated, couldnt lift up the tires from the ground. I felt totally unsecure by it, didnt even bother trying to lift it to its max position considering the shitty jack started maiking some weird noise and i could see the arm flex. Oh well what do u expect from 20bucks. Looking for a heavy steel jack with min 2.5-3ton lifting capacity. Then the shocks.

 

[Petrol Pete]

Just be safe when you get under it Do not cut corners with lifting equipment and axle stands/blocks etc.

 

[nAN3992]

I have a place behind my house where i drive the car up and can inspect it underneath. I dont like the idea of going under the car, if i have to its secured all way around. 2 jack stantd, some wood blocks, tyres blocked etc. People call me crazy, id rather not check if i can survive the fall of the car on my body

 

[pedja1402]

Hi there.

Im owning a w203 c220 cdi 110kw 150ks. 722.6 automatic gearbox. Car is fitted with DPF filter. Im having an issue with the car when accelerating. Start off is fine, when i hit from 2nd to 3rd gear and RPM drop from 2000 (2nd gear) to 1100( 3rd gear) and i hold the accelerator the car starts rumbling, vibrating. I cant point out directly from where the sound comes. Sometimes i believe its from the end, sometimes front right passenger side ( its left hand car ), There is no sound-problem at iddle when revving, when going down a hill. The sound is a combination of vibrations, rumbling, shaking. No squeaking. Its a deep tone. The sound is there only when the car shifts when accelerating and hits lower rpms on next gear, once the revs go above 1500-1600 its gone. When i drive in manual mode i keep it on 2000-2200 rpm, shift at 2500 and the sound doesnt come up. Does anyone have a clue what could be the problem?

Things ive replaced on the car
Front engine mounts - both
Transmission mount
Front sway bar end links
Front control arms - all 4
Outer tie rod both sides
Rear springs
Rear sway bar end links
Brakes are tight, there is no play on pads
The rear struts are shaggy but i believe they cant cause the noise? Will be taken care off.


I checked the hand brake cabble that is underneath the heatshield when exposed. It isnt rubbing against the driveshaft, the clip isnt broken:
All heatshields are tight, no rattling from them. The car was taken to a local exhaust shop and they fixed middle exhaust hanger-mount, was a bit lose. Rear muffler had rust rotting and its been taken care off. The sound is still there. Its driving me crazy. Does anyone have an idea what could it be? The sound only appears when accelerating from 2nd to 3rd to 4th on lower rpms. Mostly and loudest is on 3rd when accelerating on low rpms. The sound isnt there if u cruse by at 1000-1400 rpms, once u start accelerating its there. No sound when iddling, no sound when driving down a hill, no sound on ramps.. Im really clueless.

Hi

I read all your posts on this subject. I have a very similar issue with my 2001. C200 cdi automatic, exactly the same symptoms while driving. I do have additional symptom, when starting the car, it kinda "barks" for once, every time. I just had rear muffler replaced since it was rotten, but the rumble actually got worse.
Did you get it sorted out?

Thanks

 

[nAN3992]

Hi

I read all your posts on this subject. I have a very similar issue with my 2001. C200 cdi automatic, exactly the same symptoms while driving. I do have additional symptom, when starting the car, it kinda "barks" for once, every time. I just had rear muffler replaced since it was rotten, but the rumble actually got worse.
Did you get it sorted out?

Thanks

No, havent got into the issue still. Over the summer the car behaves normal, no rumbling-droning. Once the temperature drops its there. I can reproduce the sound on my own. Im driving the car in manual mode, self switching, to avoid the droning-rumbling witch appears under acceleration at lower rpms (1000-1200). Ill be changing transmission oil. The engine and transmission mounts seem to be fine but will change them anyway to lemforder ones. They are changed twice, this will be the third time. Not factory ones. So i dont thing this will solve the problem either. I dont think the problem is related to the torque converter, the part would fall apart considering im daily driving the car. Maybe a driveshaft bushing or does the differential have a bushing? Maybe the indy guy didnt change the mounts the right way ( is there a other way?) considering the best thing i can describe the sound is like if the engine touches the chasis and shakes everything.. Problem is present only under acceleration at lower rpm. (1000-1200). Above it nothing.

 

[pedja1402]

Hi again

I have an update on the subject.
I lifted my car at the local shop, and it's missing a catalysator and front muffler, there is nothing there, only a straight pipe that someone (I suppose the previous owner) welded instead (see pic). So, I think that's what causing the rumbling sound.
As for why it got worse after rear muffler replacement, the new muffler is not original part but some cheap replacement part that hasn't got the same muffling capability.
You also mentioned that your problems began after exhaust repair, so check the front muffler.
Please excuse my English.