TorontoC350

Hi all, another post here regarding a potential issue with my car (2013 C350). As the title says, I've recently noticed an excessive amount of water vapor coming out of the exhaust of the car, especially when sitting at idle. This is obviously noticeable at night, especially at drive thrus with the lights of the cars behind me shining through the cloud of steam. The weather outside has been around 15-18 degrees c (or 59 - 64), which is cooler than in the summer months although I don't see why this cooler weather would make the steam coming out of the exhaust more noticeable, especially when other cars on the road are not producing any steam. Please correct me if I'm wrong but this does not appear to be a sign of burning coolant/oil mainly because the steam is only visible outdoors and not noticeable in my garage. Nor is it visible during start up. I'm planning to take the car to a euro car mechanic next week but would still like to hear the severity of this issue and whether or not I should stop driving the car until my appointment at the mechanic. Could this be a serious problem with the engine, or could a simple tune up solve this issue? Thanks.

JettaRed

iTrader: (1)

I would say nothing is wrong. Condensation just happens and you are seeing it being burned off. Now, if you rev the car and there is a white cloud every time and doesn't seem to diminish, then it sounds like a coolant leak. BUT, you should also get a CEL for misfires. Check your coolant level and oil and make sure there is no water in the oil. As I have said before, get yourself a scanner specifically for Mercedes, either iCarsoft MB V3.0, Launch Creader Elite MB, Foxwell, or BlueDriver, and scan for code (which may be present without a CEL).

If your coolant is low, you can also get a to check for exhaust gases in the coolant. If detected, then you should be concerned. That is usually due to a blown head gasket or a cracked head.

But for now, to put your mind at rest, get a scanner and scan for any codes. EVERYONE who owns a Mercedes (or Audi or VW) should get a scanner for their brand of car. That's the first mod I ever make to my cars.

TorontoC350

Just picked up a bluedriver pro from amazon. Hopefully will be here in a couple of days. Also interesting that you say that about revving the engine because I did just that in the garage, a couple of times yesterday but didn't see anything come out of the exhaust. Coolant levels appear to be okay after being topped up about 20 days ago. Will keep an eye on it though.

JettaRed

iTrader: (1)

A blown head gasket will blow “smoke” like a fogger machine. Like I said before, probably nothing is wrong.

TimC300

Probably normal and not an issue. If oyu fluid levels are fine and not going down, and cant smell oil or coolant its probably just water/condensation coming out. I dont drive many miles and im always seeing moisture out the tailpipes. Not in summer heat but when its cooling down, even rainy humid days.

TorontoC350

That's what I was wondering too. I was driving our other car late last night and noticed all the fog/humidity in the air, but still feel like that's a lot of condensation for the car. With regards to coolant/oil smell, I've been having a hard time recognizing any of those smells. It does appear that the left tailpipe produces more exhaust than the right tailpipe and it appears to emit the regular exhaust smell (feel like I'm gonna get brain damage from breathing in all those fumes). I will be taking it to a merc/euro car specialist next week for peace of mind. Another test that I ran today was to open the coolant tank (before starting the car) and look for any bubbles while its running but I didn't notice anything unusual. I feel like the car may also be running rich but a little difficult to know without checking for codes.

TimC300

I searched for how to tell if a car is burning oil or coolant, other than the fluid levels go down, and came across this which makes sense:

Burning oil creates a lot of thick bluish white smoke.Burning coolant is more of a bright white smoke, excess fuel is darker, almost black smoke.

TorontoC350

I also noticed the following while looking around in the engine bay. does that look like a significant amount of oil on this part of the engine and what could that piece be that appears to have broken off? This car has seen multiple mechanics yet none of them appear to have noticed this part.

JettaRed

iTrader: (1)

I've had a couple of cars with either blown head gaskets (1995 Ford Windstar) or a cracked head (2005 Audi A4). When coolant leaks into the cylinders, you will see a cloud of white "smoke" and definitely smell the coolant. The car will also run badly and cause the CEL to come on immediately due to misfires. If you are having neither of these (and your coolant doesn't go down noticeably after driving a mile), then it is unlikely a head problem. To put your mind to rest for less than $40, get this (as I linked above):


Also, as I said above, get yourself a scanner and scan for codes. Don't go cheap, but get one that will scan all of the modules for your car. If there is a problem, it may not cause a CEL (yet), but there will be a code. If there are no power codes (PXXXX), then you're fine. Believe me, if you are running rich, having misfires, have a bad O2 sensor, etc., there WILL be a code.

TimC300

I cant tell anything. Stick your phone down in there and snap some photos of the engine. I do it all the time, thats how I saw my oil filter housing leaking oil.

TorontoC350

I actually ordered the bluedriver scanner from Amazon two days ago and it arrived in the mail yesterday. It shows multiple codes, two of which may be serious and where also detected by a mechanic I went to a few weeks ago who suggested I see a dealer for them. The codes are below.

JettaRed

iTrader: (1)

Now that you have them recorded, I would try clearing the codes and see if they come back. Did the mechanic clear the codes for you?

These cars are so sensitive to battery conditions, a weak or disconnected battery can throw a bunch of codes. Make sure your battery clamps are tight and there is no corrosion on the terminals.

• The most common cause of a U0100 code is a faulty battery. If the voltage in your battery drops too low, it can affect network communications, which can cause your vehicle to come back with a U0100 code.
• DTC U0111-00 Lost Communication with Battery Energy Control Module “A” will come on – Incorrect Battery Energy Control Module (BECM) harness routing causing tension on connector C4YB01D resulting in high resistance/open circuit.
• DTC U0168 Lost Communication With Vehicle Security Control Module. When monitored this DTC with the ignition on, battery voltage between 10 and 16 volts, ignition Off Draw (IOD) fused installed.

As you can see, these codes all relate to battery problems (especially code U0100). They are not specific to Mercedes, so they may be confusing. But the common theme is "battery" problems. Just Google each code.

TorontoC350

For some reason I didn't see this reply of yours but still wanted to thank you for taking the time to get back to me. I will try to clear the codes and see if they come back. The other issue that I was talking about a while ago, with regards to sluggish acceleration, was likely due to me getting used to the car and vice versa. I feel like these cars are more than comfortable being 2-3 gears higher than the optimal gear and unless you're in sport mode all the time, it's a bit more 'difficult' to get the car in the right gear/to respond right away (which is definitely helpful when it comes to conserving fuel &#128517. Thanks again.