E320 CDI - problems

[Griffo]

I have just bought a late 2000 E320 CDI Auto and discovered it has one or two faults. The one that concerns me most is the heating system. The passenger side produces little or no heat, the drivers side doesn't produce a lot! It also seems to take a lot longer to warm up than my old 1995 E280.

The response to adjustments of the (drivers) heat control is also very slow. Can anyone please suggest where the problem may lie and is it likely to be expensive to fix?

I have one or two LEd's on the dash not working (outside temp. and the clock) are these likely to be difficult/expensive to fix?

I would appreciate some views please?

 

[Blobcat]

Could be the Duovalve, pls have a look here; http://forums.mercedesclub.org.uk/showthread.php?t=18785
There are quite a few threads regarding the pixel issues pls have a search.
Did you buy from a dealer and if so did you get any warranty?

 

[Griffo]

blobcat

thanks for the reply. No I bought privately. If it is the Dual Valve, is it likely to cost a lot to overhaul/repair (through a private specialist, rather than a main dealer)?

 

[Blobcat]

I would not recommend going to a dealer, if you post up your location then you can get a recommendation of an independent MB specialist in your area.

 

[television]

http://www.detali.ru/cat/oem_mb2.as...607722.618&CT=F&cat=66G&SID=83&SGR=180&SGN=05

Item 60 in the above picture.

The clok and temp gauge canbe fixed by fitting rubber wedges on to the ribbon cables in the cluster.

malcolm

 

[Griffo]

I live in Herefordshire. I believe there's a good independent garage in Hereford but can't remember his name.

 

[Blobcat]

You may want to watch this thread; http://forums.mercedesclub.org.uk/showthread.php?t=25288

BTW saloon or estate, mileage & cost?

 

[dibdib]

I live in Herefordshire. I believe there's a good independent garage in Hereford but can't remember his name.

Try Rob Jones at Credenhill on 01432 769039 he as 18 years at a main dealer.

 

[Griffo]

Registered Oct 2000, 2 owners before me, 110k verified, saloon, leather, alloys, brilliant silver, immaculate, £5,400.

Have heard of Rob Jones (thanks dibdib), that's the chap whose name I couldn't remember. I've heard a good report of him, used to work for Eurocars I believe.

 

[Griffo]

Took the plunge and stripped the duovalve, not too difficult but nearly lost one valve when the unit suddenly separated! I put the top of the unit under a running tap and repeatedly pushed the valve plungers open. Quite a lot of small pieces of black debris came out.

Carefully cleaned everything, smeared the ridge that mates with the rubber seal in the base and re-assembled. Pleased to report no leaks and warm air on both sides now, delighted. Thanks very much for the kind help.

Still puzzled by the rubber wedge suggestion (Malcolm), what type of wedges and how does one get at the ribbon behind the cluster?

BTW, what's the opinion on price vs spec, did I pay too much?

 

[Blobcat]

Pls have a search on the forum as there are quite a few threads some with pictures on the display pixel issue.
I don't know your full spec but the price seems low/about right for a private sale, although it has a few issues...

 

[jberks]

Still puzzled by the rubber wedge suggestion (Malcolm), what type of wedges and how does one get at the ribbon behind the cluster?

I had a go but couldn't get to the ribbons. Allegedly some have had sucess wedging some rubber under the ribbon cables for the display. Feel free to try yourself. I posted a strip down thread a while back - explains how to do it inc photos.
http://forums.mercedesclub.org.uk/showthread.php?t=10956&highlight=dash

 

[Griffo]

Cheers JB, may have a go.

 

[Griffo]

There's a bit of a sequel to this:- what I didn't mention was, when I separated the duovalve, there was some wetness around the inside of the R/H electro-magnet. This was the side that controls the passenger side of the car - the defective side.

On reflection, the wetness would probably affect the magnetic field effect on the valve and this coupled with the black bits lodged inside the valve, would explain it's malfunction. What's now dawned on me is that the black bits were, almost certainly, pieces of a rubber seal that lives inside the sprung valve to stop water rising into the electric coils.

I would appreciate opinions on whether I'm right about this? If I am, then I need to replace the seal(s). This, I suspect, is not feasible, as the unit doesn't look like it will easily separate. Is it possible to just but the top section that houses the sprung valves, or is it a case of having to buy the whole duovalve unit?

 

[Griffo]

The saga continues:-

today on my return commute, the heater output temperature started to drop and no amount of 'fiddling' with the controls seemed to make any difference. After about a further 10 minutes driving, the heat started to return.

Would the duovalve produce these symptoms or is something else going on?

 

[Griffo]

Dismantled the duovalve again today and there's fluid inside the centres of the electric coil housings again. When I depressed the top of the sprung valve actuators, fluid came out of the top of the hollow stems. I notice that there are small rubber (?) mouldings in the top of the metal coil housings, are these to stop fluid coming up the stems?

I really need to establish if this is the source of my problems, any advice/opinions will be most welcome.

cheers

 

[Griffo]

Through the summer I had forgotten this problem - now it's going cold again, I'm starting to feel chilly in the car, as the heater is pathetic. I think I've read somewhere that, if you disconnect the cable to the duo-valve, it defaults to open (hot), is that right?

If so, and I get heat this way, does that indicate the problem lies with the control knobs rather than the duo-valve?

P.S. would still appreciate an opinion (or two) about the moisture inside the coil housings.

 

[Griffo]

Read this on another site:-

"Are you sure its your duo valves and not the temperature control wheels on the dashboard or the sensor in the sunroof housing.......my haywire heating turned out to be fluff and dust being stuck in the sunroof housing sensor. It works on a vacuum, ie sucking up air from the cabin, so they are prone to getting clogged.

Once cleaned my heating was back to normal......I only found this out after testing the Duo Valves with a voltmeter and finding that they were fine and then pulling out the temp dials from the centre console....the easiest item was cleaning the sensor in the sunroof housing."

First time I've heard about any sensors in the sunroof - can anyone enlighten me please?

 

[rf065]

Read this on another site:-

"Are you sure its your duo valves and not the temperature control wheels on the dashboard or the sensor in the sunroof housing.......my haywire heating turned out to be fluff and dust being stuck in the sunroof housing sensor. It works on a vacuum, ie sucking up air from the cabin, so they are prone to getting clogged.

Once cleaned my heating was back to normal......I only found this out after testing the Duo Valves with a voltmeter and finding that they were fine and then pulling out the temp dials from the centre console....the easiest item was cleaning the sensor in the sunroof housing."

First time I've heard about any sensors in the sunroof - can anyone enlighten me please?

I think they mean the sunroof housing, or rather where the the switch to open/close the sunroof is and/or interior light switch is situated. There should be open slots in the plastic housing & air is drawn in with a fan to pass over the sensor? Not sure about your model but others seem to work like that.

Russ

 

[Griffo]

Thanks for the reply. I have looked and there are small slots either side of the sunroof switch, does this sensor have any significant effect on the heating system?

I have read that the voltage from the dashboard heater control wheels to the Duo-valve, should range from 0v at full heat to around 12v at no heat (I think that's the right way round?). I take that to mean that, with no current, the default is for the valves to open fully, giving maximum heat, then as the current rises the electro-magnetic coils slowly close the valves to reduce heat.

If the above is correct, I may have another problem! I've just returned from a local garage, where I got them to check the voltages at the wiring plug that connects to the duo-valve. The readings were 12.8v at full heat setting on the dashboard controls, to 13.7v at no heat! Surely, I should have 0v at full heat?

I would really appreciate some guidance here, as I don't know whether I should replace the duo-valve and/or the dashboard controls and/or inspect the sunroof sensor???