laneshift

C240 straight off the MB dealership. Lower speeds are more noticeable, higher speeds it just starts get droned out by the wind.

I'm pinpointing it to the transmission because a) sitting on both sides of the car, it's always coming from the middle, whether you're sitting in the front and it sounds like it's under the center console, or in the back, again, sounding like it's in the center, below everything, and b) when the transmission is stressed, i.e. downshifting causing some nice revving , or the like, the clicking changes a bit in sound, but it's still there.

Anyone else witness this massively annoying clicking?

Thank you. Yes, I did search.

samaritrey

I had a click sort of thing when i got my c320. i don't know what yours sounds like but mine sounded just like a bad speedometer cable. (btw our cars do not have one) the problem according to the dealer was insulation rubbing against the drive shaft. that seems to be a common problem in early w203's. i still don't understand that insulation could make that noise but it is fixed so i don't really care. good luck getting your click fixed i know that it can get annoying but that is why you have a stereo!!

oh just thought of one more thing does it click when you are stopped. because their is one more thing that click in my car that is really annoying but it has a distinct sound. i can hear it in my car in the garage or at stoplights and if i have the radio off at speed i can sometimes hear it. let me know if that sounds more like it because i will take a pic of the thing that does it. i use to know what it was called but forgot. i think that Mercedes made a new mount to hold this thing so that it would not be so loud. i asked my dealer and decided it was to expensive to fix.

laneshift

The clicking stops when I'm at a red light or stop sign, etc. I'm really hoping it's minor and it's just some insulation rubbing, or is it major because damage could be done to either the transmission or the insulation? I probably can't get to my dealership for about another week. Because I have an extended warranty, I can only go to one dealership if I don't, hello $100.00 deductable.

When I'm stopped, though, I do here a different clicking. It sounds more like the pistons doing their thing than anything else. If I rev the slightest bit, it picks up the pace.

Thanks for the reply.

FrankW

1. why didn't you just turned around and bring it back to the dealership?
2. the different noise is called "valve noise"

laneshift

1. They've closed. We were the last to leave and we were locked out.
2. Thank you.

samaritrey

ok well i am glad you have warranty that will make things better. ok i bet the other clicking noise is the evap canister purge solenoid. it is located to the right of the abs control module. just open your hood with the engine running and you will hear it. since you car has warranty you might be able to get the dealer to replace the mount. i was told by my dealer that they updated the mount to keep the noise level down.

FrankW

get some fuel injector cleaners it would also clean up the valves since it's a 2002. also MB always have loud valve ticks.

hammertime21

drive the car and open up the center console lid, and if it gets louder and easier to hear. then it is most likely the insulaton falling down and hitting the driveshaft. (YES, it WILL make a TICKING NOISE...) it is soooo common on these cars. its a easy fix. install a bracket to hold insulation up.

LILBENZ230

Hey you paid for that warranty, get it back to the stealership ASAP.

laneshift

Update on the issue. They're trying to tell me that it's normal and it's a purge valve. What is that? And is it really that loud?

FrankW

just to be clear.

at idle with the hood up the "tapping" noise is the valve. a "clicking" noise is the purge valve.

and yes both of those clicks are normal. you can have the purge valve changed (they can't deny you), but the noise will come back.

when you are driving you are not suppose to hear either of those noise.

laneshift

Yes. The tapping noise is the valve and is normal. Thanks for the clarification.

But the purge valve will always be noisy? I can hear this thing loud and clear doing around 70 on Interstate 4. If I were to demand a replacement from MB, how long could I go before it comes back around?

Thanks man!

jturkel

if it increases in frequency as you speed up, and decreases in frequency when you slow down and stops altogether at a red light when you arent moving, sounds like what i have.

i was told it is heat insulation or something rubbing against the driveshaft.

i've had the sound for 6 years and have never been able to duplicate it for a tech at my MB dealership. w/e.......i turn up my music. and it hasnt caused any problems in those years lol.

laneshift

That's exactly what I'm trying to tell them! I feel it's much more the tranny rubbing some insulation than a purge valve. Does the purge valve tick accordingly to your speed?! I'm not betting on it.

jturkel

i dont believe so

laneshift

I'm going to have to start yelling at them I guess I'll just say that their diagnosis was and the purge valve doesn't tick accordingly to my speed.

Glyn M Ruck

Just make them fix it. No ticks in my car & I'm a pain in the AXXE

LILBENZ230

There's a TSB for that and it would infuriate me that I had to live with it. My car developed an odd noise like what you are describing and I was sure it was the head insulation thing.. took 3 dealer visits before they determined it was in fact a collapsed rear engine mount.

Glyn M Ruck

rear gearbox mount !! - You looked that up once before

BTW - Also check the flex disc on the front of the propshaft.

laneshift

Dear me. Should I just list off things for them to check?

Either: purge valve, insulation on the tranny rubbing, or a bad rear gearbox mount!

The bad gearbox mount seems common! Maybe I should emphasize on this one.

Thanks everyone.

EDIT: Adding to the list- thanks Glyn M Ruck- check flex disc on the front of the propshaft.

jturkel

idk what TSB stands for....must not be up-to-date on the lingo....perhaps you could fill me in

btw, i've had all my tranny and engine mounts replace about 3 years ago and the ticking/clicking sound persists

i was TOLD it was insulation from a buddy of mine, but MB never took a look into it b/c, you know, they have to have proof of a problem or hear it or see it to do actual work.

if i had my connections now at the dealerships back when i had my warranty, this would have been taken care of already.

Glyn M Ruck

LILBENZ230

TSB - Technical Service Bulletin

There is one out there (I don't recall the number) that deals specifically with the insulation. It said the problem manifested as noise from the transmission tunnel area. I'm not surprised the dealer couldn't duplicate. They love giving that response.

Glyn M Ruck

Come guys - you don't need a TSB or a dealer to check the exhaust heat shields. They are silver in colour as per diagram. Get under the car and see if one has become dislodged & is touching the prop under certain torque or load conditions. It's very obvious & will usually leave a nice shiney spot on the prop where it touches. This is for a RHD C240 but you get the picture. Let me know if you need other configurations but it's easy enough to work out.

jturkel

i looked under there (albeit not too carefully) when installing my headers and found nothing rubbing. maybe i'll look again sometime later when i get the car back up on a lift