Mercedes-Benz E-Class W210 - Heater/Blower Problems on my Merc W210 (98)

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Sun 9 Oct 2011 17:58
Mercedes-Benz E-Class W210 - Heater/Blower Problems on my Merc W210 (98) - Cornish Pasty

I have a problem with my blowers on my E300 TD. It is a 98 model and has the manual rotary controls. The issue I have is that it seems to have a mind of its own! No matter what speed I set the fans to they generally do not change from what can only be described as asthmatic, also they do not blow hot air. Then for no reason as far as I can determine, they will on occasion start to blow harder and then hot as well, once this happens I can adjust the heat and to a certain degree the fan speed too. What is the problem here?! Please help, I am at my wits end and coming up for winter I would dearly love to feel my hands while driving!

On a seperate note, the car also struggles to start when it is left facing uphill for a period of time, this could be 10 minutes or over night depending on the severity of the incline, this hasn't been to much of an issue as I have just ensured I park on the flat or downhill but recently it has become more difficult to start even on the flat. If I have a problem starting, if I can push it to face downhill, the car will eventually start. I have been told this is a common issue with this model but cannot seem to find a simple solution. I have replaced the glow plugs less than a year ago and I have also replaced the standard battery with a more powerful one to help when this happens but I really want to get this sorted and apart from these issues, the car is superb in every other way!

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Sun 9 Oct 2011 22:27
Mercedes-Benz E-Class W210 - Heater/Blower Problems on my Merc W210 (98) - elekie&a/c doctor

Most common issue for erratic heater blower operation is a faulty electronic fan speed regulator.This is located in thebottom of the blower motor housing and access is from the passenger footwell area .Also check that the cabin/pollen filter is not blocked,situated next to the blower motor.As for the starting issue,i would think that you have air ingress into the diesel fuel line,or even a problem with the diesel pump front seal letting air in.( I guess this is a pre-common rail diesel engine)hth

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Mon 16 Feb 2015 14:34
Mercedes-Benz E-Class W210 - Heater/Blower Problems on my Merc W210 (98) - Cornish Pasty
Thank you for the response! The fans have stopped working completely now so I will be investigating this further soon!

As far as the starting issue is concerned, this has now been fixed. The first garage I took it to was not interested in all the research I had done and instead insisted in fitting non return valves and an additional pump. After a bill of £600, they had not solved the problem. In the end I took it to my normal mechanic and he identified the pre-filter (small filter that fits into the main filter housing) was broken and letting in air. We replaced this and the problem was solved!! At a cost of less than £100!
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