[giotecno]

Guys for a few months now my MPG has been terrible, recently low 20's and now 19's I might as well have had an M3 I don't think its too much due to the weather as its much milder in London and I have been through a few bad winters and its never been this bad. I got a air filter service coming up, and have extended warranty, what components should I get checked in the car during this service? I was thinking MAF, Injectors etc anything else?? Also the car feels hesitant to drive up the rev range also feels like its vibrating/shaking more than usual as its a diesel. I feed the baby V power and BP Ultimate and always have my services done with top oil etc etc. Any input guys before I take her in?

[kaishang]

Are you driving in London? This isn't suprising. 15 mins of driving at walking pace kills fuel economy.

[HighlandPete]

Is the engine getting hot? Could be thermostats, main and/or EGR stat. Common mpg killer, especially noticed once we hit winter/colder temperatures.

Short runs don't help, as it won't heat quickly, but worth looking at the hidden menu to see what you are getting, on a heat soaked engine.

May be other issues, but a cheap place to start with a coolant temperature reading or two.

HighlandPete

[satish_141]

Originally Posted by giotecno

Guys for a few months now my MPG has been terrible, recently low 20's and now 19's I might as well have had an M3 I don't think its too much due to the weather as its much milder in London and I have been through a few bad winters and its never been this bad. I got a air filter service coming up, and have extended warranty, what components should I get checked in the car during this service? I was thinking MAF, Injectors etc anything else?? Also the car feels hesitant to drive up the rev range also feels like its vibrating/shaking more than usual as its a diesel. I feed the baby V power and BP Ultimate and always have my services done with top oil etc etc. Any input guys before I take her in?

are you driving with hand brake on

anyway on a serious note...19.3 is less, as pete says I would get the stats checked.

[dxb335d]

Problemo with car!!

But it does really depend on how and where you drive!

[zltm089]

I drive in London aswell.....currently on 15mpg....

get it checked at battersea...

[kaishang]

I can get 16mpg out of a fully warmed up 330d in London, no problems.

[giotecno]

should I give it a motorway test? i am gonna check the coolant temp today after i get home and give the girl a 30 min drive. Whats the norm reading on a warmed up car coolant temp HighlandPete?? Thx Guys

[briers]

I would defiantly give it a run.

All that cold, short town driving in traffic isn't very healthy for a diesel. It needs heat and max cylinder pressure under load.

Give it a good blast from 1.6k, low down revs + acceleration, even uphill etc. Loads the car nicely. It might need a DPF purge which it isn't managing if you are doing short, cold journeys.

DPF purges can also lead to reduced power temporarily.

[SteveF1]

Mines exhibiting the exact same traits, MPG is way down averaging 25mpg with motorway driving included.

I have recently had my air filter and crankcase breather/oil seperator replaced but this hasn't helped one iota.

Mine is showing no warning lights or fault codes but I reckon mine is due to MAF or injectors. Will be booking mine in with the dealers in the next week or two.

[E92westy]

Originally Posted by giotecno

should I give it a motorway test? i am gonna check the coolant temp today after i get home and give the girl a 30 min drive. Whats the norm reading on a warmed up car coolant temp HighlandPete?? Thx Guys

I checked mine today from cold to 85C took about 12 minutes (7 mins to the motorway + 5 mins at 70+mph).
It stayed at 85 for the next 20 mins on the motorway, then when i came off briefly went up to about 88C before dropping back to 86C where it stayed until i got home. Around 45 mins in total.
I consider this normal - hope I'm right!!

[jinjur]

Guys, i never got to the bottom of our pish mpg but with extra special thanks to HighlandPete's patience, we did get an improvement from glow plugs and a new EGR stat, albeit not final.

I have confirmed with a BMW spesh that 2 injectors are showing codes which explains our horrific startup, hot or cold, a HUGE plume of smoke too.

We also exhibit the most clattery and noisy idol and drive.

Can replace the injectors yet due to insufficient funs:computer says no scenario but will be doing so as soon as permitted.

Also, as we are on 98K miles, I maybe replacing the MAF as I am sure ts well past its best.

FYI, we get an average of 32mpg...........but i did do a motorway run to dublin last year, i reset the OBC before i left and sat a steady M'way speed.......netted 48mpg.


J

[giotecno]

I got my baby booked in to Sytner Chigwell, spoke to Aneeka. For the 14th this month to check out the MAF injectors Glow plugs ERG stat. As I am now averaging about 17MPG!!! I got Extended warranty but I am worried about them just not finding a fault and I foot the £90+ vat inspection.

[SteveF1]

Strictly refuse to pay the inspection fee regardless of the result. Williams BMW did this with me last year when I had the car in for an instability at the rear, they didn't find anything but the DTC failed two weeks after and that was the culprit. When they didn't find a fault code or visible fault the service advisor asked me for nearly £100, I said I wasn't paying it and she backed down straight away, scuttled off into the back and got my keys.

If you have a problem with the car, and I would say 17mpg on any diesel is a problem, then BMW under their insured warranty should cover ANY investigation and if they don't find anything wrong then contact BMW HQ as there clearly is something wrong.

I'm in a similar position and my cars going in in the next fortnight for low MPG amongst other things.

Just refuse to pay, see what they say and if they don't budge speak to the service manager.

[giotecno]

Guys My 320d is at Sytner Chigwell since yesterday and they have found multiple faults with the car. EGR Thermostat faulty, all glowplugs showing problems and a control box? which the service guy mentioned so my MPG is probably low due to these. Lucky I got Extended warranty as I was told the whole repair would have cost £1000+ I ll keep on how she feels when I get her back Thanks to Anneka as always for assiting and arranging thsi for me.

[jinjur]

Originally Posted by giotecno

Guys My 320d is at Sytner Chigwell since yesterday and they have found multiple faults with the car. EGR Thermostat faulty, all glowplugs showing problems and a control box? which the service guy mentioned so my MPG is probably low due to these. Lucky I got Extended warranty as I was told the whole repair would have cost £1000+ I ll keep on how she feels when I get her back Thanks to Anneka as always for assiting and arranging thsi for me.

No way 1000 dude....

I replaced the EGR stat, reckon it was like 40 quid or so and the glow plugs were around the 60 quid mark so I doubt very much that the control unit for the glow plugs is 500 quid factoring a few hundred for the massive (not) amount of labour.

Be interested to hear to this helps you though dude, I was sure the glow plugs helped mine a bit

A

[giotecno]

I totally agree jinjur with you on the price even through I am not paying for it as its warranty but apparently the Labour and Thermostat = £334 + £442 for all Glow Plugs and to fit them!!! the control box is not for the glow plugs but for the key fob issue I have as it opnly works from 1 metre away wasnt told the cost on this but dont care regardless as long as its working again.

[satish_141]

Originally Posted by briers

I would defiantly give it a run.

All that cold, short town driving in traffic isn't very healthy for a diesel. It needs heat and max cylinder pressure under load.

Give it a good blast from 1.6k, low down revs + acceleration, even uphill etc. Loads the car nicely. It might need a DPF purge which it isn't managing if you are doing short, cold journeys.

DPF purges can also lead to reduced power temporarily.

sorry what is a DPF purge? just curious to know..

[HighlandPete]

Originally Posted by satish_141

sorry what is a DPF purge? just curious to know..

Normally called a regeneration. When certain parameters are met and the ECU senses back pressure in the DPF, the exhaust and DPF will be heated up, (injection changes to give more combustion heat) and the particulate matter in the DPF burns up. And then we start all over again, to fill the DPF with particulates.

Sufficient engine temperature is one of the required parameters, so short trips and/or cold running prevents the normal regeneration sequence.

HighlandPete

[satish_141]

Originally Posted by HighlandPete

Normally called a regeneration. When certain parameters are met and the ECU senses back pressure in the DPF, the exhaust and DPF will be heated up, (injection changes to give more combustion heat) and the particulate matter in the DPF burns up. And then we start all over again, to fill the DPF with particulates.

Sufficient engine temperature is one of the required parameters, so short trips and/or cold running prevents the normal regeneration sequence.

HighlandPete

Thank Pete, you are a genius