Very Poor MPG

[Cooket3]

Hi, my new 08 reg auris is having very poor mpg. According to autitrader when i bought the car I should be getting 45mpg average. On a flat motorway which is smooth as it has been resurfaces I am only getting 24mpg at 70mph and 30 at 60mph.

Even when I use cruise control i get this poor mpg and it is not my driving style as I am being very light on the accellerator and shifting up and down when the light tells me to. Previously i had a 1.9 cdti diesel 06 reg astra and even when I hammered the throttle I was getting 37mpg minumum on average, normal driving I was getting high 40s, according to autotrader for this car I should be getting 45mpg so it was ok

I drive on the same roads everyday to work so there is no change there.

when gently driving around an empty town I can get good mpg in 3rd or 4th however when I get on the motorway in 5th and 6th this changes drastically.

Whenever I want to accellarate gently, in any gear, the mpg goes right down.

I have read other threads of poor mpg but they get in the 40s but nothing like mine

Has this happened to anyone else or can anyone suggest what it may be?

I am going to get the car serviced soon so hopefully this should help

 

Thank You

[Heidfirst]

which engine & transmission?

[craggle]

Have you done this for a while and taken an average fuel consumption or are you just looking at the display on the dash?

I have an iQ and can get the dash display to read anywhere between 12mpg and 99.9mpg but it averages around 48mpg. 

Have you checked the tyre pressures are correct too, that can make a huge difference.

Craig.

[FROSTYBALLS]

Did the Autotrader advert quote the official EU fuel consumption figures? These are not meant to be a reflection of what an owner will achieve in the 'real world', but provide standard lab based test data intended to be used for comparison between models.

[Cooket3]

Sorry for got to add.  It is a 2.2 diesel manual.

I am looking at the inboard computer both instant and average mpg

I know the auto trader mpg readings are not the real ones. But 24 mpg in a diesel is just not right at all! I'll check the tyre pressures when I get back

[Heidfirst]

T180/SR180?

These have always been thirsty due to the 5th injector but it always struck me as odd that the same engine in the larger Avensis seemed to return as good or better (still not good) mpg - but then again that could be due to the drivers being less likely to thrash it. Realistically I think that you should expect 36-38mpg average over the year if there is not a problem & you don't have a heavy foot.

AD series engines are slow to warm up - particularly noticeable at this time of year & you will probably lose a couple of mpg in the cold..

Don't trust the computer, you need to do your own brim to brim calculations.

[Cooket3]

It is the Sr 180. I'll total up the miles from last refill and do a calculation but they won't be for a week maybe.

Hopefully the computer is wrong and calculating on smaller tyres, mines 17inch, is this standard or upgraded from 16inch

The engine gets halfway on the temperature gauge which I assume is the optimum 

[FROSTYBALLS]

15 inch wheels were fitted to the base, 16 inch to mid spec and 17 inch to high level Auris. So as yours is an SR180, the 17 inch were original equipment.

[Heidfirst]

I would have thought that the rolling radius on all would have been very similar/the same (but the wider & lower profile tyre will return less mpg).

[Cooket3]

On 02/12/2016 at 10:21 PM, Heidfirst said:

T180/SR180?

These have always been thirsty due to the 5th injector but it always struck me as odd that the same engine in the larger Avensis seemed to return as good or better (still not good) mpg - but then again that could be due to the drivers being less likely to thrash it. Realistically I think that you should expect 36-38mpg average over the year if there is not a problem & you don't have a heavy foot.

AD series engines are slow to warm up - particularly noticeable at this time of year & you will probably lose a couple of mpg in the cold..

Don't trust the computer, you need to do your own brim to brim calculations.

What do you mean 5th injector? I only see 4

In 4th gear I can get 50-70 mpg going around town with no traffic. I am very light on the throttle I just cant understand why at cruising on the motorway on a flat at 60 returns 30mpg and at 70 around 26

Cruising at the same speed returns the best mpg, obviously, however when I press the throttle the smallest amount the MPG drops drasically.

I would expect 26mpg thrashing the car but not driving carefully, I looked for the real mpg and ive read 34mpg which is still very poor for a diesel. Tyre pressure is ok and the car has been serviced but no different. Air con is off and so is heaters etc. 

Any other suggestions would be greatly appreciated

Thank You

[Heidfirst]

The Toyota DPNR system fitted to the 2AD-FHV also has a fuel injector. I wonder if the system is trying to regenerate (this would explain high fuel use at higher speeds although it's never going to be a particularly economical engine)?

Don't rely on the dash computer as on cars of that age they are often out.

[Cooket3]

20 hours ago, Heidfirst said:

The Toyota DPNR system fitted to the 2AD-FHV also has a fuel injector. I wonder if the system is trying to regenerate (this would explain high fuel use at higher speeds although it's never going to be a particularly economical engine)?

Don't rely on the dash computer as on cars of that age they are often out.

What is the dpnr system and what do you mean by regenerate? Does this mean once it's regenerated mpg will be normal and how long does this take or what do I need to do to fix it?

Oh and regarding my driving style, I had a 2ltr tfsi petrol seat leon 220bhp and I managed 40mpg! This was a verybsimmilar journey to what i do now. So it's not my driving stlye

[Cooket3]

Googled it and its the DPF :-(

Can this really make the mpg so very very poor??

I have googled how drinving at high revs for a long time helps kikstart a regeneration cycle. I drove for about 20 minutes at high speed on the motorway at 3000+rpm and I havent noticed any improvement.

There are no warning lights on or anything that indicates the DPF is blocked. I just bought the car and like it but the MPG is insanely bad. I dont want to fork out £50 every other week to fill my car up.

I filled up the tank today and done 298 miles on 9.9 galons of diesel which is 29mpg!!

The strange thing is when I was on the motorway in 4th gear doing 70mph I was getting 35mpg but when I popped it in 5th and 6th!!

If I take it into a Toyota garage can they tell me exactly whats wrong? Surely if somethings going wrong on the car, some warning lights will show up? This is doing my head in

[Neilc21]

Hi,

I bought an SR180 in the last couple of weeks as a motorway cruiser and despite having another issue with it i also noticed that the MPG is *******. the scenario you have described i can totally relate too. unfortunately i think that is just how they are. mine is getting 10mpg less than i was hoping, which is like 15-20mpg less than toyota claim! if you sit at 55mph in 6th without changing gear it goes up. if you change gear or accelerate its 29-36mpg which is ridiculous. my mate has a 2.2 civic which get 45-50mpg.

[Cooket3]

I just can't get my head round how a diesel can be so shockingly poor mpg, ffs petrol sports cars can get better mpg!

[tomosllyr]

Dont forget that you're driving a heavy 8 year old 180bhp car. I agree the mpg is probably the worst bit about the car, but I can definitely put up with it. I fitted a DTUK tuning box to mine which increased the mpg from 32 to nearly 40 within 3 weeks (incidentally I'm now selling this - message me if interested).

[Cooket3]

1 hour ago, tomosllyr said:

Dont forget that you're driving a heavy 8 year old 180bhp car. I agree the mpg is probably the worst bit about the car, but I can definitely put up with it. I fitted a DTUK tuning box to mine which increased the mpg from 32 to nearly 40 within 3 weeks (incidentally I'm now selling this - message me if interested).

I just can't get my head round how a diesel can be so shockingly poor mpg, ffs petrol sports cars can get better mpg!

I understand it's a 180bhp car but look at my earlier post I drove an old 220bhp petrol and got 40mpg!

[Artiom]

What revs do you drive usually? Anything above 2k would consume a lot of fuel. My Auris averages at ~34mpg (the dashboard says so) - but I have a quite "heavy" foot as I like to feel it accelerating ;)

[Cooket3]

14 hours ago, Artiom said:

What revs do you drive usually? Anything above 2k would consume a lot of fuel. My Auris averages at ~34mpg (the dashboard says so) - but I have a quite "heavy" foot as I like to feel it accelerating ;)

I stay within the rev range it tells me to, I change up and dowe when I am indicated to. I'd say 1-2k revs

[chrismorrow]

I could be wrong, however, most diesels seem to benefit from a good high rpm drive to clear all the carbon off, if I were in your situation I would; 

check the engine air filter if it's clogged and change it

clean the EGR valve or blank it off

give it a full tank of Shell V power diesel 

take it on a long drive at 3k rpm plus, like 60-70 mph in 3rd constant for around 10 min

Get an oil and filter change and make sure the correct oil is in the car. If the wrong grade oil is in the car it could reduce mpg drastically.

people may disagree but that's what I'd do if I had this issue, I used to have the old auris 2.0 d4d and mine ran like a dream.

if all else fails then maybe a terraclean might help if the car has always been chugged around town and never had a good long run.

 

 

 

 

 

[Konrad C]

On 12/10/2016 at 11:01 AM, Neilc21 said:

Hi,

I bought an SR180 in the last couple of weeks as a motorway cruiser and despite having another issue with it i also noticed that the MPG is *******. the scenario you have described i can totally relate too. unfortunately i think that is just how they are. mine is getting 10mpg less than i was hoping, which is like 15-20mpg less than toyota claim! if you sit at 55mph in 6th without changing gear it goes up. if you change gear or accelerate its 29-36mpg which is ridiculous. my mate has a 2.2 civic which get 45-50mpg.

 

On 12/10/2016 at 11:21 AM, Cooket3 said:

I just can't get my head round how a diesel can be so shockingly poor mpg, ffs petrol sports cars can get better mpg!

I have been reading this topic with interest and learnt a few things, plus I already knew that the 2.2 litre diesel was to be avoided! 

From what I read in the two posts quoted, the owners expected performance and reasonable economy, but economy has shocked them. Also Cooket3 was not aware of the DPF and 5th injector until he was told and read up on it. Neilc21, the Honda CIvic 2.2 diesel does not have DPF and was dropped because it could not be fitted due to lack off space - It could not meet the new emissions with the DPF. Both may not know the cars history or even how the car was driven!

What I already knew about the Toyota 2.2 diesel ( and 2.0 AD), was it is known for head gasket problems! The more powerful the higher the risk.

I would do what chrismorrow has said in his post and get the engine serviced and the DPF looked at.

Diesel have had a chequered history, first slow and smokey, then when turbo diesels came along, more torque. The change to indirect injection improved things further, with lower CO emissions. Now as emissions got tighter, diesels escaped because of this blinkered fixation that CO emission was the main pollutant, but there are other emission like NOx, hydrocarbons and soot particulates. Now because authorities and the industry have realised this, the DPF was introduce. The EGR was always part of the diesel engine and these need maintenance. Carbon build up has always effected EGR's and that can effect performance and economy. The DPF can get clogged after a time and needs to regen. Slow, short, stop start journeys can cause the DPF to need more frequent regens, and the only way to do a this regen is to go for a high speed run for a good distance. The regen must not be interrupted, or the cycle has to be done all over again! Most small car diesels have been dropped because they are hardly used for long journeys. BBC's Watchdog highlighted this.

The regen cycle has different systems - VAG, Peugeot for example use and additive in a separate tank to burn off the particulates trapped in the DPF, but Toyota chose the 5th injector to do the same thing. That means the car will use more diesel during the regen cycle. The car will keep trying to regen at every opportunity. No fault lights ever show unless the car goes into limp home mode. That is usually caused by the EGR.

With VAG recent diesel gate scandal, I have read (in Honest John) that some of the effected car have had the "fix", that has left them with a drop in performance!

Also the AD (2.0 & 2.2) diesel is no longer in production with BMW diesel replacing them.

When I went to buy my Avensis, I only looked at petrol which returns mid to upper 30's mpg - I get 36 mpg with mainly local driving, even higher on longer trips. Toyota diesel were okay in principal but other brands are better.

There is a member MartyX in the Avensis forum who seems knowledgeable with engine and tuning. He is not English (writes well enough) but he might have a few suggestions. But again, just have the engines serviced with cleaning of the EGR, inlet and exhaust components.             

[Heidfirst]

8 hours ago, Konrad C said:

I have been reading this topic with interest and learnt a few things, plus I already knew that the 2.2 litre diesel was to be avoided! 

Disagree, it's a nicer drive than the 2.0 imo but you can't expect better fuel economy from a 2.2 rather than a 2.0 (my experience from 2 Avensis 2.2 estates is 42-45mpg on average, depending upon the run it can be into the 60s [once I even got 70+!]. The -FHV version however, is even thirstier especially when matched with the auto trans. I wouldn't buy an -FHV myself.

From what I read in the two posts quoted, the owners expected performance and reasonable economy, but economy has shocked them. 

As I previously said it always surprised me that the same engine in the larger, heavier Avensis is usually reported as returning slightly higher mpg. Nobody should expect to get the European test mpg in real road use (the differential is especially bad for hybrids, PHEVs etc,).

What I already knew about the Toyota 2.2 diesel ( and 2.0 AD), was it is known for head gasket problems! The more powerful the higher the risk.

Only a small % though & pre Sep2009 - e.g. my old 2.2 T25 has just passed it's MOT at 9. Lots of engines have their own known "common" failure points e.g. BMW swirl flaps, Ford Focus diesels (PSA derived) etc.etc.

It certainly pays to do research before buying a car as to what you can realistically expect (mpg, common problems etc.) 

           

 

[Konrad C]

16 hours ago, Heidfirst said:

 

Scott thanks for you additional points and correcting me.

Like the old 1ZZ engine oil burning issue, on a small percentage and not every AD suffered the head gasket issue. Also you have the experience of driving the diesels which I admit I have not. I have been in all of the Avensis 1.8 petrol engines. I have driven other diesel engines, and like the Renault/Nissan 2.0 litre engine. very smooth and strong torque at very low revs. I think I need to experience a Toyota AD diesel. 

One thing I have to say, Toyota are still generally reliable.

 

[Cooket3]

On 12/12/2016 at 2:59 AM, chrismorrow said:

I could be wrong, however, most diesels seem to benefit from a good high rpm drive to clear all the carbon off, if I were in your situation I would; 

check the engine air filter if it's clogged and change it

clean the EGR valve or blank it off

give it a full tank of shell V power diesel 

take it on a long drive at 3k rpm plus, like 60-70 mph in 3rd constant for around 10 min

Get an oil and filter change and make sure the correct oil is in the car. If the wrong grade oil is in the car it could reduce mpg drastically.

people may disagree but that's what I'd do if I had this issue, I used to have the old auris 2.0 d4d and mine ran like a dream.

if all else fails then maybe a terraclean might help if the car has always been chugged around town and never had a good long run.

 

 

 

 

 

The fuel filter has been changed along with the air filter. The oil filter required a tool to get it off so will do that soon. Engine oil changed and put in the reccommended oil, 5w i think. As mentioned before I drove for 20 minutes with high revs and I put a tank of BP ultimate diesel.

 

For the first half a tank i for around 220 miles but the second half plummeted and ended up getting 363 miles on the tank, which worked out at 36mpg, still better but still absolute dog * I cant get my head round why the first half tank did well but the second half was crap, I do the same routes every day and driving style is the same.

 

Both rear callipers have also been changed, one before I bought the car and one after as the calliper was sticking. I have read another forum on this and someone was getting 500+ miles on a tank nearing 600!!

[Heidfirst]

As I mentioned earlier I would suggest that an average of 36mpg in winter is probably all that you should expect.

Not sure on the Auris but Toyota fuel gauges aren't always directly progressive.