C207 E350 CDI - Hot drivers footwell- DPF?

[BigMark]

Whilst driving my 2009 E350 CDI coupe I've noticed a few times that the side of the drivers footwell up to the centre console (side near ashtray and gear lever) gets really hot.

At first I thought this might be a gearbox cooling issue, but the passenger side seems fine, so then I started wondering if this is DPF related and normal?

I've never owned a car with DPF's before, I know they regenerate by getting hot enough to burn off the particulates, so is this just what mines is doing, or is there an issue as the drivers side of the centre console and footwell does get rather hot.

Also the other day after I got back home from a short drive into town I could smell the heat and hear the exhaust system cooling down despite doing an 80 mile motorway journey just an hour prior. Would it really need to regenerate?

 

[MrGreedy]

I wouldn't expect the DPF to soak so much HEAT thought to the cabin, and I thing it is more centrally located in the engine bay. You might have an issue or need to do a blend flap motor reset for your AC system? If this is something that can be done on the C207 (It deffo could be done on the w203, but must admit I've not found the need to try it on the w212).

 

[BigMark]

Found a thread with the exact same issue on.

Extreme Heat from transmission tunnel C207 (e500) | Engine

E5oo by bh13coupe posted Sep 16, 2017 at 12:29 PMHi Guys after a short drive this mornining i felt on my left leg extreme heat coming through the trouser leg. I felt the side of the transmission tunnel and it was very hot to touch. the heat was only on the driver side and not anywhere else. I...

forums.mbclub.co.uk

So it's not my DPF but heater system blowing hot down the drivers side to the rear vent regardless of the settings.

All I need to do is work out how to fix it.

 

[MrGreedy]

Found a thread with the exact same issue on.

Extreme Heat from transmission tunnel C207 (e500) | Engine

E5oo by bh13coupe posted Sep 16, 2017 at 12:29 PMHi Guys after a short drive this mornining i felt on my left leg extreme heat coming through the trouser leg. I felt the side of the transmission tunnel and it was very hot to touch. the heat was only on the driver side and not anywhere else. I...

forums.mbclub.co.uk

So it's not my DPF but heater system blowing hot down the drivers side to the rear vent regardless of the settings.

All I need to do is work out how to fix it.

As per my post above, try some searches here and maybe on YouTube for blend flap, hvac, heating reset on your model, or maybe duo valve sticking (not sure if your model has a duo valve).
On the older models it was simply a case of holding certain buttons for several seconds. I fear the more modern models might be more involved, if it can be done at all.

Hopefully someone will come along shortly who has your model and can chip in with their experience.

 

[BigMark]

I need to identify the location of the flap.

When I bought the car I noticed the ashtray lid was sitting high on one side and wouldn't close. So I removed it and the gear surround and extracted £24 of coins from all round the gear selector, under the ashtray, and tucked down in various places.

I'm just wondering if there's a coin or two somewhere near the flap jamming it?

 

[MrGreedy]

There are 5 blend flap motors (servos, also called stepper motor) on our cars (I've had a look, and the general arrangement looks the same on the 207 and the 212).
They are item No. 190 in the attached picture, and they bolt on to various places on the large unit, which houses the flaps themselves.
The large unit will sit on the transmission tunnel, underneath the centre of the dash, and behind all the centre panel buttons and COMAND unit.

The flap motors will unlikely be easily accessible without dismantling the dash, which will be an involved job. No doubt the centre armrest glove box will have to come out first, then peeling back carpets and various items from the dash itself, allowing you to squeeze in a hand and cut yourself to shreds whilst you try to manipulate something in an impossibly small space. I got to 'enjoy' this process on my old C class.

The first port of call I suggest is getting in touch with someone with either Mercedes STAR diagnostic, or a good quality hobby diagnostic like iCarsoft, and seeing if you can identify any fault codes, or failing that, looking at live data to see if there is anything obvious showing up with the HVAC system and its operation. If you can fault find to pinpoint the problem precisely before starting down the dismantling path, I strongly recommend it.

HVAC (heating ventilation aircon)

 

[MrGreedy]

I've just Googled this for you. This is what I've read in a few minutes.

So, no duovalve on the 207 or 212 (it was on the 211 E class under scuttle panel). It's flapper motors as I describe above that are solely responsible for hot and cold distribution.

Options are (cut and paste from elsewhere mbworld):
- I have posted the 99% chance fix several times now, and this will be the last time. There is a stuck flap on one of your flaps. Lower you temperature to the lowest then back to the hottest until the flap lubricates itself into working.
- After trying your 99% chance thing, for at least 50 times, I understood that I am at that 1% left. But as you told, that it is totally flap fault, I used endoscope through middle vents to look at them. And I found something that no one would ever guessed. There was stuck pencil in AC flap actuator. I don’t know what previous owner was doing or thinking and how it is even possible to throw it in there. But after 4 hours of extremely hard work of picking it out, problem was fixed. Of course flaps needed new calibration, but after that, heat is coming as new.

Given the considerable amount of change, it could well be physically jammed. From the above comment online, you might even have something that's inside the flap box e.g. snapped air freshener or phone mount fallen into the HVAC control box.

Get scan with STAR/Xentry done to at least pin point which item is causing the issue would be my recommendation.

 

[MrGreedy]

 

[BigMark]

I've just Googled this for you. This is what I've read in a few minutes.

So, no duovalve on the 207 or 212 (it was on the 211 E class under scuttle panel). It's flapper motors as I describe above that are solely responsible for hot and cold distribution.

Options are (cut and paste from elsewhere mbworld):
- I have posted the 99% chance fix several times now, and this will be the last time. There is a stuck flap on one of your flaps. Lower you temperature to the lowest then back to the hottest until the flap lubricates itself into working.
- After trying your 99% chance thing, for at least 50 times, I understood that I am at that 1% left. But as you told, that it is totally flap fault, I used endoscope through middle vents to look at them. And I found something that no one would ever guessed. There was stuck pencil in AC flap actuator. I don’t know what previous owner was doing or thinking and how it is even possible to throw it in there. But after 4 hours of extremely hard work of picking it out, problem was fixed. Of course flaps needed new calibration, but after that, heat is coming as new.

Given the considerable amount of change, it could well be physically jammed. From the above comment online, you might even have something that's inside the flap box e.g. snapped air freshener or phone mount fallen into the HVAC control box.

Get scan with STAR/Xentry done to at least pin point which item is causing the issue would be my recommendation.

Thanks for all the help.

I removed the centre console entirely last night and found another £6 in loose change but the location of the flap is about 6 inches higher up, so I don't think it can be jammed by coins

I'll try tonight going from max to min temperature repeatedly (probably not the best day to sit in a car with the heating on high but needs must)

If that fails then the car is going to MSL tomorrow for the week, so hopefully a savvy tech will have a solution.

 

[MrGreedy]

As per the comments I found on another forum, I think the options now are:

It simply needs some sort of reset with STAR.

Something has fallen through the vents and is blocking flaps on the inside.

The stepper motor swirl flap motor is faulty and needs to be replaced.



It was worth looking on the exterior and stripping the trim, because as well as finding some cash, you've likely ruled out more cash jamming something on the outside of the air distribution unit.

 

[AndrewOl]

£30 in loose change that’s impressive! All I found (eventually) was a used NO gas canister which was rolling back and forth inside the heating duct that feeds the rear. Has worked its way all the way up to underneath the front passenger footwell. Oh how I laughed after pulling the centre console to bits just to find out I didn’t need too!