El Cid

My 2010 "E" requires that the driver go through a cumbersome, complicated procedure to place the car in neutral and exit with the car staying in neutral. This is required if you use a conveyor type car wash (says so in the Operator's Manual). If it is not done, the transmission locks into park for entire trip through carwash. Incidentally, the instructions for this procedure in my Operator's Manual are incorrect or confusing. It says to leave ignition ON when it actually requires leaving engine running at start of procedure. I tried backing off one "click" and when I opened door, it went to Park.

Most carwashes change attendants frequently. And you have to let them drive car to end of conveyor. I have resorted to printing out instructions and attaching them to steering wheel. I also tip well.

Another problem with using any carwashes is that you have to set the recirculation ON to keep water out of the cabin filter and HVAC system (Says so in the OM). Unfortunately, when you turn the car off, it automatically turns the recirculation off. Have to warn attendant to turn it back on.

Are these more examples of dumb German overengineering? I think so.

Did wash it myself, but no longer able to do that.
OM also says do not use a touchless car wash that uses caustic spray. As if a car wash is going to have a sign: We Use Caustic Spray.

Haffster

The HVAC bit is interesting. I recently had the fan motor die on my C300 - was replaced under warranty - and the service guy at the dealership actually told me to switch off the HVAC when in a car wash. Seemed to make sense - will check what the OM says.

noka

Didn't locate info about enabling recirculation mode for car wash in my manual, but will need to check again.

Update: I found the reference:
! Make sure that: the ventilation/heating is switched off (the OFF button has been pressed).

Q: What did I potentially destroy if I already washed the car several times in the past few months without doing that?

edbro

The manual for my 2014 says to turn the HVAC off.

Haffster

Good to know - that's exactly what the service guy told me.

mnje350

Never use the car washes that pull the car through. Don't want the washer material draging across the finish of the car. So, i use the "touchless version". So this has never been an issue.

So while I am sitting in the carwash while the touchless system operates I hit the recirc button and close the doors to the wind tunnel air that theoretically dries the car. Not a big deal.

However, the manual will also tell you that touchless carwashes are bad for the finish due to the harsh chemicals used. I have not had a problem after four years on my black 2010 E350.

I think that washing by hand using the three bucket method is the safest albit the most labor intensive for those who can invest the time and effort. I'd opt for the touchless. So far no problems.

Russ103

X2

I ran it through one touch less wash once this winter while the HVAC was set on "auto"

Did I get the cabin filter wet? Hopefully that's the worst that can happen...

El Cid

Interesting that newer models say to turn HVAC off whereas mine says to engage the recirculation mode.
Have been using the conveyor system with hanging cloths for about 30 years and over 20 vehicles. Never had a problem with scratches, swirls, etc.

homeofstone

^ +1 re: car wash

Alex.currie44

Ok, from my experience on 6 E's from 1987 to present, I hand wash when I can and I never use a car wash that touches the car anywhere. I cannot always hand wash in the winter so I use touchless washes with underspray.
I have seen these conveyor types grab suspensions and do damage. Brush types in our environment can pick off tiny grit if not a very small stone in the brush and then it scratches following cars. The felt drape types are really bad for that so not car wash that is not touchless.
All soaps have some element of caustic material to them. That is what dissolves the grease from the road. The first soaps were animal fat saponified with Caustic Soda.
I always select the lowest level of wash with wax as a finish in the winter.
I clay bar my cars twice a year and continue to be amazed that even after a wash of any type how much crap sticks to the paint.
I wax twice a year as well.
As to the HVAC issue, where did that come from? Never have and never will do anything abnormal in a car wash. The water cannot get that far in any significant way. I change my own cabin filters ($30 vs $68 + Labour at the dealer) and they never show any signs of water damage.

Alex.currie44

Recirc is the exteme left button beside the rear window defogger on the 2011 models.

noka

Thanks, I know the button location but was wondering what damage could result. In my manual, it says to shut the system off.

El Cid

The Operators Manual says it, at least for 2010 model. Other posters here say dealers and manuals say turn system off for newer models. If it wasn't possible, MB would not have cautions about it.
Apparently the super downward force of the water, especially in touchless systems could force water into the ventilation system and/or soak the cabin filter. About a year ago, a couple of people on this site posted problems with mildew odor or a wet cabin filter.
Just more strange German/MB engineering.

Alex.currie44

No access to my manual, but I never bother and never have had an issue. Just sayin'.

mnje350

What color is your 2010? Mine is black and I am **** over protective of the finish. Hence the touchless. I must admit, many times I have not turned the car to recirc or killed the HVAC before the touchless wash and I have had the mildew odor in my car. It has been good for the last year or so but I have also been more careful about putting the HVAC on Recirc. Perhaps that is the difference.

My S class is white so it has gone through the "traditional wash systems." and has the same tranny system as my E and has never been a problem with the conveyor. I never even really thought about it. The operator of the car wash, in other words a kid, has hooked it up however. It is a "High End" car wash, or so they will try and have me believe, but it has also never been a problem.

El Cid

Mine is Palladium Silver, which is actually somewhere between silver and steel gray. However, have used automatic car washes for dark gray and dark red cars with no problems. Have not purchased a black car in over 25 years. Beautiful when clean, but much harder to keep clean.
I do check out the black cars that come out of the car wash I use and have never seen one with swirls, scratches, etc. Most of them are MB's, BMW's and Lexus'.

Airmousam

That would be truly remarkable. Swirl marks will not be seen unless you are close to the car. If you're admiring black cars exiting a wash, you will very likely not see them. Have you ever seen a car with swirl marks? If so, where did they come from? I'm on my 3rd black Benz in a row, all 3 had to have paint correction for swirls (2 were under 20K miles). Here's a shot of the 2 that I have now. As careful (read over the top ****) as I am, I still have a few subtle swirl marks. pi$$es me off. If I took either one thru a regular car wash (the ones where you follow that filthy mini van thru) they would have noticeable swirl marks for sure. We've had fun with this topic before Cid, all in good fun

El Cid

I don't go and lean over the cars, but I will stand within a few feet of them. Actually, may get closer as I go up to mine to give instructions to the attendants to NOT use the tire gloss on the tires.
If I had a black car, I would have a lot more concerns. This is another reason why I don't have black cars anymore.
Guess a lot depends on the car wash too. Be glad you can still hand wash yours and get a real quality job. A car wash will never be as good. I have even tried the $75 hand washes and found them inferior.
Yes, all in good fun and maybe to present the options to others. DIY with three buckets and expensive products is absolutely the best way to do it. No question. Wish I still could.

Arrie

I don't think there will be any real damage done. The issue really is that the drain tube in the bottom of the cabin air intake is so small that in car was the excessive amount of water that is sprayed on the car can overwhelm it leading to the water level to raise to the air intake opening and enter inside when the fresh air intake is open. This can wet the air filter and water can leak in the passenger side foot well, which has happened twice to me when I forgot to engage the recirculation. Neither one is a big issue for me as the blower runs constantly in my car and I drive long enough trips so the wet filter dries out. The spots on the floor mat come off on the brusher.

RNBRAD

Touchless washes use a alkaline chemical that's sucks the life out of any rubber or trim, I refuse to use them or any auto wash for that matter. Regular self serves in my area lack pressure that I like. I just purchased a gas Generac 6602 One Wash system. You can adjust the pressure from 2000 to 3100 and has 3 spray tips and soap dispenser. Makes washing a breeze, no long lines, no dirty bays that often gets my car dirtier and no feeling hurried by those waiting. Best money spent!! I wash everything at home as well as my home.

Russ103

Same here. Can't beat DYI vs an auto wash.

Just purchased a foam cannon for my pressure washer. Can't wait to try it out this weekend.

El Cid

Another example of inferior MB engineering. No other car I have ever owned had this problem. That includes Swedish, Italian, Japanese, Korean and most American makes.
Not to mention the silliness about how to leave it in neutral.

noka

Another view: Maybe MB is on to something. I have owned numerous BMW's and a big complaint by many owners across various models was the AC having and odor like 'smelly/dirty socks'. The dealers try various things to clean the system and some companies developed products to try. Some people suggested various methods e.g. running the blower on high after driving on a humid day, in an effort to dry things out before shutting the car off, etc. Sometimes people had success and sometimes not. I don't think any of my BMW owner's manuals specified to set to recirculated air or to shut off the HVAC system when washing the car (but I am not 100% certain). I have also heard of other brands suffering from this on occasion.

Maybe MB found out a possible cause and to prevent that ugly problem, they added instructions to the guide. A possibility anyway.

Airmousam

Makes sense, good post!

Arrie

This actually did happen to my Dodge pickup big time wetting the whole floor but the reason was the drain was totally plugged. After it was blown clean has not happened again.