MikeDC

Others have described a ticking or diesel sounding engine noise and I'm trying to determine if that is what I am experiencing. Most describe hearing the noise when the engine is cold. I hear the noise after the engine has warmed up. Some reports have also indicated that replacing the engine mounts or the purge valve. My Mercedes mechanic (not a dealer) checked both and said they are fine and also said that it is a common problem with that engine. Perhaps that's true, but I only started hearing it in the past few months and I've had the car for 4 years. It only has 44,000 miles on it. Any suggestions for next steps? Really appreciate it. I can't stand the noise.

Kevwood

I have some slight lifter noise but nothing major, I'm going to replace the lifters when I do the cams anyways. Question for you Mike, when your mechanic said "that it is a common problem with this engine", what did he mean? What is the problem he is making note of?

I'm interested to hear what he has to say. Ticking sounds like lifters, 'clacking' could be far worse, aka, bearings.

MikeDC

There are a few folks who have described a similar noise. To me, it reminds me of a diesel engine. I would not personally call it ticking cause that sounds too light. It clacks, louder than my '67 Chevy Nova used to. The mechanic said that it is a common problem with the 5.0 liter, but I am going to call the dealership tomorrow.

Kevwood

I'm still wonderng what he means by common problem... The common problem isn't the noise, it's what's making it. Interested to hear what the dealer tells you. Hope it's not bearings or a rod knock.

MikeDC

Ah, I see what you're saying. I asked what was causing the noise and they had no answer. There is a TSB that seems to address this: 070021D. "ENGINE TICKING (PISTON SLAP) NOISE COMPLAINTS WHEN ACCELERATING BETWEEN 1200 AND 3000 RPM. MODELS E500, SL500, CLK500 MY2003." Of course it specifies MY2003 and mine is a 2004.

I will update here once I speak with the dealership. Thanks for your help!

kostas86

I also have a 2004 CLK500 and just hit 44k miles.
Mine does the same thing.
We are currently looking at 2 issues, bad fuel with weather change or oil change needed a lot sooner than the computer recommmends.

How often do you change your oil?

mikata

Mine also ticks(from the little box on the right side of the engine bay), dealership said that it does that on bigger engines, but that's just BS.

MikeDC

I purchased the car in 2007 with 39,000 miles on it. Obviously I don't put many miles on a car. I change the oil with the regular service intervals (i.e., service B, service A).

I would not classify it as a "tick." That implies a light or quiet sound. This sounds like a diesel engine. The noise is "clacking." The noise appears after the engine warms up.

mralf

Do you know if your indie. mechanic is using the correct synthetic oil?
Maybe they use the wrong oil or non synthetic and oil is breaking down sooner. Also wonder if our cars need valve adjustments.

kostas86

My wife even noticed it and said it sounded like a 80's benz diesel motor
Curious to see what the dealer tells you as I probably have same issue.

MikeDC

He uses Mobil-1

MikeDC

Well the dealership called today. The noise I was hearing was the CATALYTIC CONVERTER!! How my mechanic did not hear that is beyond me. However, the best news is, it's covered under WARRANTY!! Woo-hoo!!! Thanks everyone for your input in trying to help me get this sorted out.

kostas86

Are you serious? My brother was telling me to check my exhaust and I was like no way is it that, but I guess I'll have to get mine checked also. I hope that is the issue with mine and not the lifters.

dr_npz

Great info man. That can be usefull for many guys here

dragon_27

lol i had the same problems too. the ticking noise turned out to be just the actualator (i think that's what the mechanic said) ticking, located on the top right engine side, which is normal but gets louder as the car ages, but the other noise was in fact the catalyic converter so i had to delete that and now, the problem is solved...

kostas86

Perfect excuse for a cat delete

renard sylver

I have a 2003 clk500 and my car was making the same valve tapping noise. it stopped after i changed my oil by mixing weight (half 0w 40 and half 5w 30) also make sure the filter is installed correctly. when installing filter push it up all the way until you can't see the line on it anymore. I haven't heard the noise since,by changing oil every 6,000 miles.

betrezra

My ml500 makes some lifter noise. 66K miles.

MikeDC

So this clacking noise has returned. Does the CLK500 have TWO catalytic converters? I think it does, but I'm not sure.

Also, I believe the dealer is required to replace a faulty CAT up to a certain number of miles. Anyone know what the mileage limit is?

THANK YOU!

Rudeney

The CLK500 has two catalytic converters - one on each side. Also, there are a pair of "secondary cats". On your car, those may actually be cats, but on later models, they were just resonators. As for the EPA-required emissions warranty, it's 80K miles/8 years, whichever comes first.

Staccamil

Very helpful I was getting really upset about the noise I thought I was going to have to have some engine work