Loss of coolant and misfire rough running when up to temperature

[Merc1967]

Hello there,
I'm new to this forum and wondered if anyone could offer any pointers please as to what may be wrong with my Merc E220cdi blue efficiency - it's a 2011 auto estate. When it's up to temperature I'm getting a pulling/juddering/misfire type issue, particularly between 35-50mph when I start to accelerate. I've also started getting the 'top up coolant' warning message every ten days/couple of weeks and I have to top it up around 700-1000ml.
Any thoughts please as to what may be going on? Many thanks for your help, I appreciate it.

 

[markjay]

Welcome.

The two issues might be unrelated, but if they are related, then you might have a leaking head gasket.

Either way, the car will need to go on STAR diagnostic computer - this isn't a DIY job. Someone on here might be able to recommend a good specialist in the Cheshire area.

 

[Smiley]

The two problems may be separate issues - but it could also be that you have coolant leaking into the automatic transmission fluid via the radiator. I would suggest that you get the car looked at by a MB specialist. I would avoid a main dealer unless you have very deep pockets.

 

[andym2]

Obviously the first thing is to find out where it's leaking. If it's the radiator you'll see the coolant dripping out of the holes in the liner tray under the engine. The transmission fluid cooler and radiator are joined together as one piece and there were a few radiators that leaked internally and contaminated the transmission fluid with coolant. These were around 2006 I think and on mine (2008) the problem was just that the radiator was just leaking due to age and corrosion. Changing the radiator was actually quite easy; one of the benefits of having a 2.1 litre 4 cylinder engine in an engine bay designed for a 5 litre V8 is that there's plenty of room. You can get a new radiator made by an OEM manufacturer for about 1/3rd of the MB price from ECP. The hose connectors to the radiator are a sort of quick fit type. Take the time to figure out how they work before you try and remove them, otherwise you'll need new hoses which only come from MB and cost almost as much as the radiator. You will lose a little transmission fluid, but not enough to make a significant difference to the level and you can't top it up as the filler is sealed. Probably a good idea to get the transmission fluid changed anyway. A vacuum filler makes refilling the cooling system easier, but isn't essential. A co-incidence maybe but the thermostat also stopped working at around the same time. No real symptoms other than it took forever to warm up.

 

[Tonygw]

I am guessing this is the OM651 engine? There are two VERY common places for them to leak coolant, 1 is the water pump at the front of the engine, look for signs of dry crusty coolant around the pump/pulley belt area,
the other is the fuel filter housing which is connected to the coolant temp. Locate the fuel filter (top right of engine) and look down to the bottom of the housing for pools of coolant collecting.

You may need a torch and god eyesight to see down the side of it. I would put money on it being one of those that's leaking.

The pump often leaks more when cold and you can see it dripping, mine was, the replacement pump is a metal pump over the original plastic pump[ which seems to fail. What kind of mileage are you on?

 

[Tonygw]

As to the rough running, have you checked the basics, fuel filter, air filter etc? A partially blocked fuel filter could cause this.

 

[Gooner198o]

I am guessing this is the OM651 engine? There are two VERY common places for them to leak coolant, 1 is the water pump at the front of the engine, look for signs of dry crusty coolant around the pump/pulley belt area,
the other is the fuel filter housing which is connected to the coolant temp. Locate the fuel filter (top right of engine) and look down to the bottom of the housing for pools of coolant collecting.

You may need a torch and god eyesight to see down the side of it. I would put money on it being one of those that's leaking.

The pump often leaks more when cold and you can see it dripping, mine was, the replacement pump is a metal pump over the original plastic pump[ which seems to fail. What kind of mileage are you on?

Hi i am getting the top up coolant message every 2 to 3 days. I'm driving my car to work at the moment with an engine light also.

I got my air compressor and radiator changed about a few weeks ago. I was told there could be an air lock and to just top up and hope for that to sort itself out. I am not about 4-5lt of distilled water and coolant down and still getting these messages.

I noticed my car has started jerking (more than normal) from my gear changes (two to one) after the Air compressor and radiator were changed. I've asked the specialists who did the initial job to take the car back and have a look.

Could my coolant be leaking in to the auto gearbox? Am i damaging the gearbox by driving the car? The last thing I need it want is the gearbox to get messed up.

They also did a big job on the manifolds and the error code I'm getting is p2015. This car has really drained my love for driving. Every time I've sorted an issue out another issue seems to pop up.

Any help would be appreciated.