[SteveF1]

My 320d has begun to suffer again after another harsh winter. Last year took its toll on the MPG were it averaged 35mpg through the cold conditions and it also refused to or took an age to start which led to 3 of the glow plugs being replaced under warranty. The car ran fine through last summer but took a turn for the worse this winter and I'm now starting to feel the pain again.

First off the mpg has been atrocious. It averaged 35mpg last winter and this winter in similar conditions and near exactly the same driving conditions its averaging 25mpg. Admittedly I don't do huge miles daily and I know I don't get the engine sufficiently heated to make the mpg work but it managed 35 last year and has lost another 10 mpg this year - how?

The engine has become very lumpy at idle, it will physically rock the car from side to side every 15 seconds or so, smooth out and then violently shake again. This has combined with blue/dark smoke coming from the exhaust on startup (which appears to disappear after the engine has warmed up) and the smell of engine smoke/fumes in the cabin on startup when the blowers are on. I have never had the smell come in the cabin before, surely the microfilter should prevent this?

The final straw is that there is now a whining sound coming from the engine bay. I can't be 100% sure but it appears to be coming from the nearside and happens when the car is hot or cold, its pretty much constant now. It happens when under power, the more throttle the higher the pitch on the whine but also can be heard when slowing while still in gear. Drop out of gear or dip the clutch and the noise disappears.

The car had an oil service, replacement oil filter, air filter, diesel/fuel filter and oil seperator done a couple of months ago and is not due anything for some time. I also used Fuchs Titan GT1 oil so good stuff and a BMW dealer carried out the work but the car ran fine after the service and before the cold spell hit.

I'm done with this car but any ideas guys as its still under the BMW insured warranty.....

[dziqsek]

Go to dealer - your car still have warranty rightx?

[Walesy]

My idle is lumpy and it does it when it is cold, during the summer it is fine so I take it it's the colder weather that causing it. In the morning I get a slightl blue puff from the exhaust also, only when it is cold.
I took it to the dealer and they said it was totally normal, I even recorded the exhaust on my phone to show them and they said it was normal especially in colder weather (not oil, it's diesel in the cylinder). The idle thing didnt raise it's head at all when I took it to the dealers (typical). But the cars runs fine other wise.

Let me know how you get on, I will be interested to see if I got the brush off.

[HighlandPete]

You need a visit to the garage, could be several things. Rough running could be fuelling, injector(s), egr issues. Mpg could involve the above issues and/or could be coolant temperature related, main or egr thermostats are typical culprits.

Do you suspect the whine is clutch/gearbox related? If it is engine related it will be there 'changing' with engine revs, clutch in or out of engagement.

HighlandPete

[SteveF1]

I never actually thought it would be clutch or gearbox related to be honest, I get the impression its either engine or ancillary but am not technically minded enough to say what exactly. Its definitely only just started after the snow left, gets higher in pitch when accelerating but can be heard on the way down. It only happens whilst in gear, its vanishes when out so could be transmission.

Pete re the coolant/EGR can you explain that area a little more because if it is that I'd like to be clued up before taking it to the dealer. I took it to them last year re the MPG and threw the injectors/Maf sensor argument at them and they were initially taken aback that I knew what they were. On checking them they said the results from diagnostic test in this area were 'within tolerance' but they admitted they had not physically checked any of these components as that would 'cost money' and because there was no fault code BMW wouldn't pay out.

I'm taking the car to Darren Woods BMW specialist next week for some modding work so I'll ask him for his expert opinion too before taking it to BMW.

[lemans 330d]

if its under warranty why go to a specialist and not the dealer?

[SteveF1]

Because I'm having mod work done thats being done by the Indy next week, he can give me an opinion before I decide to go to the dealer. If he says its trouble then its going back, if its not then I'll leave it because I must have been back to the dealer 30 times in the past 15 months and I'm sick of them.

I'm not going back unless I really need to warranty or not.

Just out of interest Lemans you said in another post that you have had the dealer reprogramme your car so that your modded LCI headlights will illuminate the halos on opening the car with the fob. How much did that cost out of interest?

[HighlandPete]

Originally Posted by SteveF1

Pete re the coolant/EGR can you explain that area a little more because if it is that I'd like to be clued up before taking it to the dealer.

A lot of BMW diesel model E90/E60 engines are heavy on fuel for no apparent reason. Checking the coolant temperature can indicate a failure of the thermostat(s). We have two, the main 'stat and one on the EGR cooler, either (or both) can be the culprit. Often it is the easy, low cost one, the EGR 'stat.

Temperatures run low, some even struggle to get into the 80's. Should be around 90 when there is decent heat in the engine. And not drop out as some engines do mid driving.

To access the hidden menu, to read the temperature:

http://e90.wetpaint.com/page/BC+hidden+menus?t=anon

HighlandPete

[Walesy]

Originally Posted by HighlandPete

A lot of BMW diesel model E90/E60 engines are heavy on fuel for no apparent reason. Checking the coolant temperature can indicate a failure of the thermostat(s). We have two, the main 'stat and one on the EGR cooler, either (or both) can be the culprit. Often it is the easy, low cost one, the EGR 'stat.

Temperatures run low, some even struggle to get into the 80's. Should be around 90 when there is decent heat in the engine. And not drop out as some engines do mid driving.

To access the hidden menu, to read the temperature:

http://e90.wetpaint.com/page/BC+hidden+menus?t=anon

HighlandPete

As a matter of interest buddy, is there a pic of the EGR stat anywhere and how much does it cost to replace, I would do this to see if that stops mine being lumpy.
Also, where is the main water temo stat on the 320d?

[HighlandPete]

You can obviously track it via RealOEM parts list. For a quick look, for various models google 'BMW EGR thermostat' and click images. Got some associated parts illustrations on page one. It's the cylindrical/flanged unit, fits to the EGR cooler.

HighlandPete

[F104]

In my experience low 80's can be normal in freezing temps depending on how you drive. It takes my engine 20mls on the motorway to get to high 80's. First E46 320d's had a webasto diesel burner heater because of this. Don't jump to conclusions based on a one-off hidden OBD menu read out.

320d thermostat is on the waterpump inlet. Follow the lower hose from radiator back to engine.

There is no such thing as an EGR thermostat. N47 320d's have a modulating EGR valve - no3. No2 is a feedback sensor, no5 operates the bypass valve ( gas flows thru a channel in the bottom of the cooler element where it is not cooled by coolant - to assist fast warm up). No1 is the cooler, 6 and 7 coolant ports

[Tunna_uk]

Originally Posted by SteveF1

Just out of interest Lemans you said in another post that you have had the dealer reprogramme your car so that your modded LCI headlights will illuminate the halos on opening the car with the fob. How much did that cost out of interest?

+1 I am interested in that as well.........

[HighlandPete]

Ooops, F104 is correct for the later N47 engines. I keep forgetting we need to clarify which model engine we have, now that the later engines are also in the loop for showing up issues.

So who's with an M47 variant that has both 'stats?

I also agree on not just taking one reading, we really are talking about some heat soak. Some have found (M47 engines) the temperature goes rise correctly, but will drop out and then not get back up to full temperature again, even on long and warmer trips.

HighlandPete

[F104]

HighlandPete - my apologies re my EGR thermostat comment. Out of interest I looked up the M47 and you're right, it has a thermostat in the EGR assembly. I now wonder how that works, as on a cold engine you want EGR to heat up the coolant..
I had assumed BMW moved straight from the pneumatic on/off valve on the E46 engine to the pneumatic modulating one on the N47

cheers,

[paulwtech]

I recently insisted my BMW dealership check for EGR Cooler failure whilst my car was in for service after coolant went low twice with no warning and with no apparent escape! Coolant pressure test was ok; technician diagnosed egr Cooler failure & the dealership are raising a claim case with BMW even though my build doesn't currently appear on the UK BMW EGR Cooler recall technical campaign!
More info here: https://www.bmw.co.uk/landingpages/b...e-recalls#gref
And here: https://www.bmwblog.com/2018/10/23/b...lion-vehicles/
My build is a 2014 F31 320D N47 efficientDynamics auto
My advice; if you're coolant goes low for no apparent reason; take it to a dealership & demand a test regardless of whether your build is on a recall list or not, & fight your corner before anything catastrophic & costly occurs! BMW press release: https://www.press.bmwgroup.com/globa...86151EN/417072