Chase230

When I start my 2005 C230k SS (Automatic Trans.), and immediately turn the air on, it sounds real rough, almost like an egg beater sound. But when I turn it on with no AC until it warms up, it sounds fine. Also if I bring the AC all the way to "6" it sounds really bad. Can anyone tell me what the problem might be?

LILBENZ230

The A/C compressor may be seizing up and putting extra load on the engine.

Hogger

Mine does the same thing.
Read some threads that suggested the idler, and tensioner pulley's. So I replaced them, and it still does it.
A/C works great, just sounds like crap on start up.
Mine also will go into a limp type mode sometimes with the A/C on. My screen doesn't say "limp mode", and it doesn't throw any codes, but it cuts the power in half.

sammydragon3

maybe the alternator pulley not giving the power fully

Glyn M Ruck

Normal!

Chase230

So glyn, it sometimes squeaks, and some people said its a sprag bearing.But it's normal? I was gonna take it to Carmax to get work done.

Chase230

Thanks guys and gals for your replies, it's given me some piece of mind. So I don't have to wait for the engine to warm up before I turn AC on? thanks!

Hogger

Normal??

Normal that these problems would eventually happen?
Or normal because everyone's car, even yours makes those noises. We just have odd cars since our "normal" problems only just recently started?

Glyn, I've always respected your input, and advise... But this has me puzzled.

torake

Had that chirp for 6 months and 10000km until I changed the sprag bearing/alternator freewheel. Chirp is gone and nothing else seems damaged.

Chase230

torake, how much was it for you. I can do the currency conversion my self. Thanks!

Chase230

And lilbenz230, have you fixed it yet, or is it fine to leave it?

torake

DIY: Pulley 50 EUR, pulley tool 20 EUR

Stealer: OEM Pulley 120 EUR and 1-1,5 hour labour

Glyn M Ruck

Sorry - a bit too hasty in my reply. A certain amount of rough running until warm & stable is typical with A/C load on the 4 cylinder engines. Even Matt's car does this - so does Phil's. See previous threads in this regard. As mileage rises the throttle bodies & actuators wear & make this worse as do soft mountings. On Phil's car the throttle body was replaced & it improved things but some of it is the nature of the isolation mountings.

The 4 cyl engines are a little clattery until warm & clearances normalise & all the emissions stuff shuts down. Even the V6's are noisier.

Unusual noise is best checked by removing the Poly V belt & checking accessories if the noise disappears.

Check idlers, tensioners, Alternator/bearing, HVAC compressor itself.

Good luck.

Chase230

Glyn, I don't know how to do all that, but what you said was to get rid of the noise, so if I can live with the sound, could I just leave it? Or could it end up causing premature wear, or more costly repairs down the road? Thanks! You've been a big help!

Chase230

Thanks torake, big help!

Glyn M Ruck

As long as you have no timing chain rattle at start up you should be OK.

There is some evidence on this forum that a sprag bearing failure on the alternator on an M271 can take out the HVAC Compressor drive. I have not personally seen a case of this.

Chase230

How does the timing chain rattle sound? Sorry about my lack of knowledge! Or if you have a sound clip, that would be even better! thanks!

Hogger

Understood, thanks Glyn.

Chase, do a search for timing chain rattle. Should answer your questions. It's a fairly loud rattle, or clanking sound for just a second or two after start up, until the oil pressure builds.

Chase230

Ok, thanks Hogger, Glyn and everyone! I'm getting a state inspection in a few days, will they catch if something's wrong? Again, thanks!

LILBENZ230

What the hell does that even mean ^?

Anyway, yes the M271 is especially noisy when cold A/C on or not. I wouldn't say mine runs roughly, it's just noisy. Then again, all my engine mounts are relatively new.

Chase230

I meant if when i get my c230 inspected, will they say, "You need a new sprag bearing, or will they say, the car looks good." By the way everyone, just hit 90,000 miles today! Lol

Opelveve

engine vibration when AC + gear D ...on red light

plz help
i replace 2 hoses under air filter and cleand TB in\out side AND cleand MAF
no error codes
plz help

KSKarl

That sounds like what Glyn described as normal.

JK325es

I did new serpantine belt, idler and tensioner pulley to get rid of chirping noise which ended up being the alternator. Got new alternator installed. This resulted in extreme amount of vibrations with the AC on, forget turning on the AUTO climate button function as it felt like a caged animal was under the hood. I was told to have the AC compressor inspected, the pulley and operation was fine.
-This made me think it was something else.
This really started to bother me as this engine is only a 1.8 litre 4, why the heck should it run so poorly. All maintenance of the engine (oil, filters, plugs are current) No check engine lights. So I moved on and replaced fuel filter which made engine run a bit smoother but not a marked improvement. AC vibrations still resulted. I also noticed if I turn on my rear defroster for the window or if I pull up on the window switches when the windows are already raised the engine would get a slight electrical interuption and shutter very very minimally however it was present anytime I did this.
-As a last effort before I figured I would stop worrying about it I replaced my ignition coils (All four) and the car runs and responds very smoothly. Extremely minimized the vibrations with the AC on. I plan on having my engine transmission mounts replaced in the next month and expect the car to run very well by that point.