Passat 1.6TDI Bluemotion not delivering good mpg

prosaic

I have one that is only giving 45-48 mpg. It's only 16 months old with 30,000km on clock and has been run fairly gently.

It seems way below what it should be giving. Any thoughts as to why? Could it be due to the engine being poor from the start?

It is still under 2 year warranty and I wonder if there are grounds for calling on that.

EDIT: I'd really appreciate any real firsthand experience of performance from owners of this model so that I can compare.

Chuck_Norris

prosaic wrote: »

I have one that is only giving 45-48 mpg. It's only 16 months old with 30,000km on clock and has been run fairly gently.

It seems way below what it should be giving. Any thoughts as to why? Could it be due to the engine being poor from the start?

It is still under 2 year warranty and I wonder if there are grounds for calling on that.

Out of curiosity, what sort of driving are you doing, as that's going to have a major impact on you mpg.

Sleepy

What's in the boot?

prosaic

Doing average 15 to 20km/day - a combination of shorter daily trips (3 to 20km) and every week or two doing a longer journey (100 to 400km).

In the boot, generally not much, maybe 5 to 20kg

Chuck_Norris

prosaic wrote: »

Doing average 15 to 20km/day - a combination of shorter daily trips (3 to 20km) and every week or two doing a longer journey (100 to 400km).

There's your problem.

Stallingrad

MPG sounds pretty much exactly where I would expect it from what you've described. Keep in mind the manufacturers figures are pure fantasy and you can take at least 10mpg off whatever they claim.

Joe 90

It's a big, heavy car, what do you expect?

-Corkie-

Chuck_Norris wrote: »

There's your problem.

Next problem will be a clogged DPF...

Mar4ix

-Corkie- wrote: »

Next problem will be a clogged DPF...

If it is clogged, then warning light will be illuminated on dash, which really you can't ignore.

Passat is a bit too big for 1.6 tdi.

My wifes polo 1.6 tdi is just about alright .

op, by your mileage, it seems to be engine all time in regeneration cycle, which means, turbo charger makes higher pressure, to get higher temp in DPF get clear it. ... if you driving in city, no good either.

short journeys, big car, small engine ... leads to no good MPG .

Bpmull

My mums 2011 octavia 1.6tdi does 54mpg mixed driving in and out of town about 450 km per week. Although the passat is a bit bigger so it will do less 48mpg seems about right for your type of driving.

mailforkev

Joe 90 wrote: »

It's a big, heavy car, what do you expect?

A big, heavy car with a little diesel engine.

I would have thought close to 50 mpg when you're doing mainly short trips is as pretty much as good as it gets.

prosaic

ok. The consensus so far here is that the numbers are reasonable. I had read elsewhere that even under suburban driving conditions (not frequent stop/start) that values in mid to high 50s could be expected. VW quote higher values, e.g. 45mpg urban, 68mpg extra-urban. I'll have to look into it more.

The manual mentions there is a DPF sensor and that an indicator tells when it needs cleaning at higher revs. The longer journeys on motorway every week or two should provide the required cleaning, no? Maybe need to consider occasional higher revs over 2k?

Mar4ix

would be special liquid topped up which goes in exhaust system for those passat ? not in polo , but not sure about passat.

I am not sure about that, worth check out.

Francie Barrett

Joe 90 wrote: »

It's a big, heavy car, what do you expect?

Rubbish.

Francie Barrett

Mar4ix wrote: »

Passat is a bit too big for 1.6 tdi.

Not if you're looking for decent economy.

Francie Barrett

mailforkev wrote: »

A big, heavy car with a little diesel engine.

I would have thought close to 50 mpg when you're doing mainly short trips is as pretty much as good as it gets.

More nonsense.

langdang

Francie Barrett wrote: »

Rubbish.

Ah now, she's a bit hefty alright.

MuppetCheck

Francie Barrett wrote: »

More nonsense.

At least elaborate.

Are you saying that short town trips the car should be returning in excess of 50mpg?

Mansized Wreath

It's a massive car with a small engine, what do you expect? The 1.9 or 2.0tdi is the only engine to have in a car like a passat.

Francie Barrett

MuppetCheck wrote: »

At least elaborate.

Are you saying that short town trips the car should be returning in excess of 50mpg?

No, I am disagreeing with the notion that the reason for unsatisfactory MPG is due to the lower powered engine.

Francie Barrett

Mansized Wreath wrote: »

It's a massive car with a small engine, what do you expect? The 1.9 or 2.0tdi is the only engine to have in a car like a passat.

Nonsense.

PaulKK

Francie Barrett wrote: »

Rubbish.

Francie Barrett wrote: »

More nonsense.

Francie Barrett wrote: »

Nonsense.

Wow. Nice constructive posts there.

Gerard93

Don't want to go off topic but a query on the DPF, I have a '07 Nissan Pathfinder would this have a DPF fitted, unfortunately all I am doing at the moment is town driving and a bit concerned about DPF (if fitted) getting clogged as I understand very expensive to get replaced etc., if it fails and may not be doing the required driving to get it to clear itself.

I have to check the owners manual to see if there is any info on this.

Thanks.

-Corkie-

Francie Barrett wrote: »

Nonsense.

Is that a automated reply to everything??? He is right I drove one and it was gutless..

Francie Barrett

-Corkie- wrote: »

Is that a automated reply to everything??? He is right I drove one and it was gutless..

Excuse me, I must have missed the bit where the OP complained about performance. Can you point me to that bit?

Thanks.

Francie Barrett

PaulKK wrote: »

Wow. Nice constructive posts there.

At least it's more constructive than just making up things that are blatantly untrue.

Kalel

Francie Barrett wrote: »

At least it's more constructive than just making up things that are blatantly untrue.

Nonsense

Francie Barrett

OP: The issue here definitely isn't the fact that this car is a 1.6. Lots of people on spritmonitor are getting high-50's MPG with mixed driving in the same model. It's also unlikely to be mechanical either given that the low mileage of the car. I suspect that if you want better MPG, then you're basically going to have to be more careful and slow down. Adjusting your driving style is by far the most significant thing you can do to improve economy. I suggest that you always have the on-board computer MPG setting switched on so you can constantly monitor consumption.

The AA has loads of tips on eco-driving.

En route

Easy does it: drive smoothly, accelerate gently and read the road ahead to avoid unnecessary braking
Decelerate smoothly: when you have to slow down or to stop, decelerate smoothly by releasing the accelerator in time, leaving the car in gear
Rolling: if you can keep the car moving all the time, so much the better; stopping then starting again uses more fuel than rolling
Change up earlier: don't labour the engine but try changing up at an engine speed of around 2,000 rpm in a diesel car or around 2,500 rpm in a petrol car. This can make such a difference that all cars in the future are likely to be fitted with a 'Gear Shift indicator' light to show the most efficient gear change points.
Cut down on the air-con: air-conditioning increases fuel consumption at low speeds, but at higher speeds the effects are less noticeable. So if it's a hot day open the windows around town and save the air conditioning for high speed driving. Don't leave air-con on all the time but aim to run it at least once a week throughout the year to maintain the system in good condition.
Turn it off: electrical loads increase fuel consumption, so turn off your heated rear windscreen, demister blowers and headlights, when you don't need them
Stick to speed limits: the faster you go the greater the fuel consumption and pollution. Driving at 70mph uses up to 9% more fuel than at 60mph and up to 15% more than at 50mph. Cruising at 80mph can use up to 25% more fuel than at 70mph.
Don't be idle: if you do get caught in a queue, avoid wasting fuel – turn the engine off if it looks like you could be waiting for more than three minutes.

Some other tips. Don't accelerate towards junctions or red traffic lights if you have no traffic behind you. When coming towards a hill, I find that by giving it a little extra boot before you come to the rise can give you that little extra moment to get you over the hill without having to really push down on the gas. Stop using your brakes needlessly! I am always amused when I see people braking when taking gentle bends in the road when all they need to do is lift off the gas a little.

prosaic

I had a Passat 2.0litre before this and while the current modle is a little lower powered, in most situations I'm happy with the power available. I'm not so inclined to speed or overtake and generally stay within the limits.

I do drive economically as suggested so I don't think it's that that is the problem.

The current model does indicate gear changes: down when revs below 1000 and up when revs above 1800. There's also 6 gears, giving lower revs at speed.

I'll have a look at spritmonitor.

While driving on the motorway, the fuel consumption reading varies very widely, depending on whether on incline, accelerating or decelerating. It can go from one end of the scale to the other. Driving at 110 - 115km/h, the average looks to be reading around 12-16 km/l or 35-45 mpg. Driving at ~50km/h gives 15-19km/l or 42-53 mpg. These figures are not very accurate as I haven't been monitoring these figures closely up to now. I've been basing calculations on longer term fuel fills and mileage. It'd be nice to be able to log data to a computer for better analysis too.

Gerard93

It'd be nice to be able to log data to a computer for better analysis too.

You could try this, gives you option to compare for likewise models etc.

http://www.fuelly.com/

whippet

I've done just over 35k miles on my Superb estate with the same engine and I am averaging over 60mpg on my daily commute (the guts of 90 miles round trip)

As for those going on about the engine is too small for the car ... Not true at all ..what it isnt going to win any races its adaquate and does the job .. Efficiency is what the engine is for. I am coming from my previous car being a 200bhp hot hatch.

For the OP ..from your description of your daily commute you shouldnt be driving a diesel anyway

mickdw

In my opinion, that engine in the passat is not good. It can seriously get bogged down if caught off turbo.

Zubeneschamali

Francie Barrett wrote: »

The AA has loads of tips on eco-driving.

My tip, get used to MPG in the 40s, and do the exact opposite of everything the AA recommends. Drive or stop, no dawdling. Forget upshifting at 2000 or 2500 rpm, use the engine up to at least max torque to get up to cruising speed briskly. Please use aircon and window heaters for full visibility.

Francie Barrett

whippet wrote: »

I've done just over 35k miles on my Superb estate with the same engine and I am averaging over 60mpg on my daily commute (the guts of 90 miles round trip)

As for those going on about the engine is too small for the car ... Not true at all ..what it isnt going to win any races its adaquate and does the job .. Efficiency is what the engine is for. I am coming from my previous car being a 200bhp hot hatch.

For the OP ..from your description of your daily commute you shouldnt be driving a diesel anyway

Hear hear.

Most of the people who have commented on this thread don't have a clue and don't even own a Passat.

MuppetCheck

Francie Barrett wrote: »

Hear hear.

Most of the people who have commented on this thread don't have a clue and don't even own a Passat.

Neither does the guy quoted. Do you have a 1.6 diesel Passat? What are you getting?

I'm asking as my father is looking at one.

prosaic

I talked to VW. They said that I could go have a fuel efficiency test done at a VW garage (at my expense) to tell if the engine is performing. I guess this will be my next step.

prosaic

Zubeneschamali wrote: »

My tip, get used to MPG in the 40s, and do the exact opposite of everything the AA recommends. Drive or stop, no dawdling. Forget upshifting at 2000 or 2500 rpm, use the engine up to at least max torque to get up to cruising speed briskly. Please use aircon and window heaters for full visibility.

Not sure I like your advice. Blasting down the road from one set of lights to the next generally acheives little other than a brief ego enlargement. I'm getting a little old for that.
I also like to do a little to be kinder to the environment.

Joe 90

Francie Barrett wrote: »

Rubbish.

Nope, it takes a given amount of power to accelerate a given mass to a given speed. It takes a given amount of power to overcome drag at any speed. Heavier car means more power required, bigger car means more power required. The size of the engine, within reason, has a lot less to do with it than the size and weight of the car. Simple physics.

Joe 90

Francie Barrett wrote: »

Excuse me, I must have missed the bit where the OP complained about performance. Can you point me to that bit?

Thanks.

Fuel consumption is a measure of performance.

langdang

prosaic wrote: »

I also like to do a little to be kinder to the environment.

Get a lighter car!

prosaic

langdang wrote: »

Get a lighter car!

I have space requirements that a smaller car might not meet. Other than that, I'd be happier with a smaller car.

Zubeneschamali

prosaic wrote: »

I also like to do a little to be kinder to the environment.

Why are you driving a new car, then? Manufacturing a new car is worse for the environment than running your previous car.

prosaic

Zubeneschamali wrote: »

Why are you driving a new car, then? Manufacturing a new car is worse for the environment than running your previous car.

We're heading off topic a little and I'd prefer to stay to the main point I've been asking about. Another thread could be the place for other topics like this. Anyway, this is my woolly take on it. The old car was heading into a less reliable age and I don't want to be patching it up. Someone else will be driving it on towards it's end-of-life. If I continued with it, it would go towards reducing the supply of second hand cars and increasing their price thus pushing someone towards deciding to buy a newer rather than older car. I did say 'a little more kind', given the circumstance of me driving this particular car. If the car lived up to its specs of low fuel consumption, it would be considerbly more friendly to the environment. I won't respond much further on the environmentally friendly topic as it's not the focus of this thread.

galwaytt

whippet wrote: »

...my daily commute (the guts of 90 miles round trip) ...

prosaic wrote: »

Doing average 15 to 20km/day - ...

That's the reason right there: the trips you're doing are too short for engine to get up to max efficiency.

In fact, that kind of mileage doesn't justify buying a diesel at all, and as mentioned, unless you break out of that pattern, then as sure as eggs is eggs, you will be dealing with DPF issue eventually.

Idbatterim

the consumption isnt going to be great, very short trips, engine not getting up to ideal operating temperature, will lead to lower fuel economy, make sure you have correct tyre pressure, oil and filter are changed regularly. Most importantly read the road ahead, i do all my driving in Dublin and most of the time, Im just coasting up to the next set of lights...

http://www.fuel-economy.co.uk/toptips.shtml

the claim of cold engine using twice the fuel that a warm one will is fairly, shocking, is it a totally oTT claim?

Joe 90

And the fact is that for a given car doing a particular set of journeys, who is driving is going to make a huge difference in fuel consumption.

Edit to add: The manufacturers poster figures will probably have no resemblance to what a particular person gets in real life but I would consider them pretty valid to compare one car with another. If car A uses 10% less than car B in the quoted figures I would assume that car A would use about 10% less than car B when I drive it. However, I would not expect the absolute figures that I get in real life to math the quoted figures. I might do better, pretty unlikely, but would probably do worse.

Joe 90

Idbatterim wrote: »

the consumption isnt going to be great, very short trips, engine not getting up to ideal operating temperature, will lead to lower fuel economy, make sure you have correct tyre pressure, oil and filter are changed regularly. Most importantly read the road ahead, i do all my driving in Dublin and most of the time, Im just coasting up to the next set of lights...

http://www.fuel-economy.co.uk/toptips.shtml

the claim of cold engine using twice the fuel that a warm one will is fairly, shocking, is it a totally oTT claim?

I've never heard the claim that a cold engine might use twice the fuel that a warm one will but if you think back to the days of carburetors with chokes and ignition systems with points and centrifugal advance it might not have been that much of an exaggeration.

galwaytt

Joe 90 wrote: »

I've never heard the claim that a cold engine might use twice the fuel that a warm one will but if you think back to the days of carburetors with chokes and ignition systems with points and centrifugal advance it might not have been that much of an exaggeration.

Indeed. .or that starting a car takes as much fuel as leaving it running for 5 minutes....

jayc12

If you look at honestjohn website about cars real mpg, owners of the passat estate averaged 50 mpg.

Zubeneschamali

jayc12 wrote: »

If you look at honestjohn website about cars real mpg, owners of the passat estate averaged 50 mpg.

Not on 5 mile urban trips, though.

lomb

The main cost and expense is not the 5mpg your possibly loosing. Its the 30k car thats depreciating at the rate of 6k a year and the interest on 30k of 1500pa..