2010 Toyota yaris 1.3 Petrol poor MPG?

[redhyper]

Hello first time posting but I'm been lurking on these forums for a while and found the users here to be knowledgeable and helpful. I've owned a Toyota yaris 2010 1.3 petrol since febuary and the MPG has been worse than my 1.8 yaris. I only get around 220 miles per tank of fuel. I drive around town and dual carridgeways where I do journeys that can last 30+ minutes there and back. The trip computer reads 38mpg when I'm just driving around town and goes into the 40s when driving in 6th gear for a while. The car was serviced two months ago, has four premium new tyres which increased the mpg a bit as it was worse before. I've reguarly checked tyre pressures, driven calmly, and taken it on longer journeys but nothing has helped and in fact the MPG is now getting worse. There are no leaks under the car or any I can see around the engine. I've checked the spark plugs and removed some carbon but look in good condition to me. The first time I get into the car it kinda struggles to start but is fine after that. The start/stop eco mode only works randomly. I don't have any aircon, radio etc on while driving.

I bought this car for the £30 road tax, good mpg figures and 6th gear but it's been really disappointing. I feel like I'm going to have to sell it to buy a car that is better on fuel which this car is supposed to be. Can anyone help me out here and can give me an idea of what is causing the poor fuel economy.

Many thanks.

[Cyker]

What's your oil level on the dipstick? How's the oil usage on the car?

Being a 2010, it'll have the 1NR-FE engine which is known for having poorly designed piston rings - Symptoms are high oil usage (Mine was using a litre a month!) and, as it gets worse, reduced performance as the rings no longer seal properly and combustion force escapes past them instead of pushing the cylinder down.

 

[FROSTYBALLS]

Honest John's Real MPG gives a range of 36-59mpg for the 1.33.

https://www.honestjohn.co.uk/realmpg/toyota/yaris-2006/133-vvt-i

The stop/start system will operate in what seems like a random manner, and there are a number of factors which affect its operation (eg. whether the Battery is fully charged, and so on). Rather than relying on the car for fuel consumption figures, do a brim to brim calculation, which will provide more accurate information, and report back.

[TonyHSD]

I think for this car 40mpg is perhaps on the normal side for town driving and some A roads. If doesn’t start first time you may need to look at fuel air mixture, something about spark plugs again even if they look good if they have 50+ k miles better put a new oem ones, then throttle body, maf sensor check  and clean. , replace air filter if it’s dirty. Also if the car burns oil it may clogging the lambda sensors and cat converter. You can try wynns catalytic converter and lambda sensor cleaner. The type of oil you have in the car, I believe the correct one is 0w20. Also you may want to try 99 E5 fuel, this later 95 E10 especially from some supermarkets is not a good fuel, my car just does not like it at all.  

[flash22]

scan it for codes, have a look at the o2 sensor voltages from cold and the long term and short term fuel trims

is it hard to start from cold ?

[Cheaky]

In case this info helps:

I have a 2007 Yaris 1.3 (2SZ-FE engine) with 80k miles.   I average around 45mpg doing mostly 4-5 mile trips on open road, typically 30-50mph depending on traffic.  Your 38-40mpg may be normal if this includes a lot of stop-start driving in traffic, or higher speeds.

 

[redhyper]

Thanks for the replies. What I'm getting annoyed at is only getting 220 miles per tank and that seems to be getting lower and lower. The first time I checked one spark plug it did have oil on it. Then about month later I checked all of them and they had no oil on them. I've tried scanning for codes and found nothing. I know that the Battery is not a start/stop one but it still looks newish. I've owned a bunch of hot hatches and they had better fuel economy than this car. There's got to be something wrong with it.

[flash22]

If just 1 cylinder is rich (black sooty deposit on the plug) change the plugs if it's on its originals they have been upgraded to a new part due to running issues oem are Denso

 

what engine do you have ?? 2SZFE or 1NRFE ? If in doubt, drop me a PM with your vin

I would be looking at the injectors

 

 

[FROSTYBALLS]

Range is irrelevant really as this can adjust depending on drive style, type of driving, etc. What people need to know is the fuel consumption you're actually getting - which is why I suggested you do a brim to brim calculation of mpg which is more accurate than the car's estimate.

[TonyHSD]

Indeed, and these cars has a small fuel tanks too. You will need true mpg calculated full tank to full again. Only then you can see if there are any issues with consumption or issues with range. On some newer models like rav4 in USA for example many had problems with fuel tank capacity, for some reason they could only fill up just pass half the tank leaving 1/3 of the tank empty and causing them to refill more often. You may look on that matter too. 
Good luck 👍

[Parts-King]

I have seen plenty of fuel filler pipes rotten these, you get fuel spills from the neck when going around corners, that certainly would not help the MPG, check that out 

The fuel tank thing was USA specific, it did not affect European cars 

[redhyper]

Yes it's the 1NR FE engine. So should I buy new spark plugs? I'm not sure how much that will help with fuel economy. I've counted the miles I've done fueling up from low to max many times. I know how many miles I'm doing per tank and it's about what the gauge says if not less.. Air filter, oil was changed on service. There's know why I can check things that was suggested like MAF and throttle body as I only can do basic things on the car like change spark plugs.

The car does actually have another problem that has become worse is that it makes creaking noises when steering is on full turn. I took it to a garage and they said it's nothing to be worried about. But It doesn't feel right.

[flash22]

originals will be SC20HR11 these are now replaced with SC16HR11, a worn plug will lead to a weak spark in turn you end up with unburnt fuel or a poor burn - in time that will burn out the Coil(s)

with these Iridium plugs, the points wear down and gaps open up

[redhyper]

Hello. A bit of an update. I managed to clean the MAF sensor by watching youtube videos. It seemed to make a small difference in terms of engine performance. As for the spark plugs I bought the SC16HR11 ones and the bolt is a lot bigger than the NGK ones in the engine. I'm not sure if these are the right ones as my spark plug tool doesn't fit on it now. I pulled only one of the spark plugs out and despite me cleaning it this month it is covered in carbon and it has some oil on it. Although using a cloth to clean inside where the ignition coil sits no oil appears on the rag.

The spark plugs I bought say 'IKH20TT 4704' on them.

[APS]

On 5/24/2022 at 11:59 AM, redhyper said:

The car does actually have another problem that has become worse is that it makes creaking noises when steering is on full turn.

Hard to know what you mean by creaking, it's all very subjective. But, high pitched ticking or clicking noises when on full lock would indicate worn CV joints. This would need addressing.

The creaking you describe could also just be the rubber gaiters squealing a bit on full lock. This is not much to worry about.

BTW - we used to have a Yaris just like yours. A 2010 model with the 1.33 (1NR-FE) engine - from new. I'd say you'd normally get 40MPG around town and closer to 50 on longer journeys. Your black spark plugs do not sound healthy. Could be CO2 sensor - this could be cleaned. But it may be OK since you have not got any fault codes. I'd also get someone to do a compression test on the engine. It's quick/cheap to check and fundamental to the engine's efficiency.

[Guest]

I don't know what sparklers you have bought but the plug shown is a Denso SC20HR11 which, other than Denso, Iridium, SC20HR11 and Japan, there's nothing else. This one is out of my 1NR FE engine and replaced by a set of SC16HR11.

Should be 14mm across the hexagon flats and require a 14mm socket.

[venomx]

On 5/22/2022 at 9:37 PM, redhyper said:

I bought this car for the £30 road tax

£30 ? Mine was nearly £200 for the year 

[Cyker]

That's because you have the pre-2009 1.3L engine, which is more reliable but has less peak power and higher emissions.

Toyota shoe-horned an emission compliance engine into the 2009+ Mk2's, what we call the 1.33 (The extra 3 is important!), or the infamous 1NR-FE oil-guzzler!

Your tax may be higher but feel content in that you have a much more reliable engine! (Mine was burning off a litre a month before I got rid of it! Thank goodness Toyota sell 0w20 really cheap or that would have been much more painful on the wallet!)

 

[Mooly]

The oil burning in my 1.33L (Auris) is bad running at about 1 litre in 900 miles I would guess.

Poor starting is a reported symptom of this problem (along with pre-ignition) although I've never experienced poor starting myself. I would have to say the mpg is as good as ever despite the oil burning and despite running on 10w40 oil. Its currently showing around 51.3mpg and a brim fill shows the reported figure to pretty accurate. It also feels as quick if not quicker than when new.

The Stop/Start has never worked well from new (as in from day 1) and it would often go days without ever cutting in even though journeys were often in the 20 to 50 mile range.

A new Battery fitted last year fixed that. Now it cuts in every time, every day. The op mentions his Battery not being rated as suitable for Stop/Start and that is important on the 1.33L because of the way the charging is managed. The Battery goes for periods without being significantly charged in normal driving with the alternator only cutting in when decelerating for example. It does this by altering the alternator output voltage, around 12.6 volt when not charging and 14 when charging.

If the battery fitted is a standard flooded type then it may have a short life and deliver poor performance.

One very important thing is to do a proper mpg check with a brim to brim fill up and calculate the mpg yourself and not just go off the trip. 

[Al D]

Best economy tactic is on hot day with air con on do 40-50 mph for dozen miles in 6th on A road with few traffic lights with a reset of trip computer. If round town you think get 40 mpg, that's brilliant. I've had diesels that wouldn't do that. The 1.33 engine I believe had piston issue fixed at time yours built. If you insist on a change of brand Suzuki Swift 1.2 would be fine am sure.

[flash22]

8 hours ago, redhyper said:

Hello. A bit of an update. I managed to clean the MAF sensor by watching youtube videos. It seemed to make a small difference in terms of engine performance. As for the spark plugs I bought the SC16HR11 ones and the bolt is a lot bigger than the NGK ones in the engine. I'm not sure if these are the right ones as my spark plug tool doesn't fit on it now. I pulled only one of the spark plugs out and despite me cleaning it this month it is covered in carbon and it has some oil on it. Although using a cloth to clean inside where the ignition coil sits no oil appears on the rag.

The spark plugs I bought say 'IKH20TT 4704' on them.

SC16HR11 are correct, these engines run like carp on anything but Denso plugs you have to use a 14mm 12 point socket (thinwall) to get down the plug hole

eg. https://www.ebay.co.uk/itm/254950678682

IKH20TT 4704 are too cold a plug

[Guest]

17 hours ago, Cyker said:

or the infamous 1NR-FE oil-guzzler!

Really? Mine doesn't use any discernable oil between changes. Maybe I should be worried. Or was the issue resolved at some stage prior to early 2014?

[Cyker]

It was mainly a problem in the earlier ones - Certainly the first Yaris to have it from 2009 are extremely prone to this problem.

By the time it was put in the Mk3, they'd fixed the problem so you should be okay. I think yours is the last version of the engine before they switched to the 1.5 so it should have the least issues of that model of engine.

On a complete tangent, I really wish the Mk4 had the single windscreen wiper the Mk3 has! No matter what I do I'm always getting sweep lines in the middle! It was so annoying yesterday in the heavy rain!!

 

[1.33]

To the OP: Try filling up at a different fuel station and compare your MPG. I used to do 100 miles a week in commuting and was getting 48-50mpg before E10 fuel was introduced. It then dropped to 42-45mpg. My MPG improves slightly when filling up with more expensive E5 super unleaded, and when using a non-supermarket fuel station. I'm averaging around 45mpg on local runs, or 50-54 on longer runs at 65mph in 6th gear.

My car has 136k miles, has a noisy timing chain on startup, and smokes on acceleration. I've cured this temporarily by changing the oil every 6 months and using a stop smoke additive. I use 5w30 oil instead of the recommended 0w20. The car is reliable and can still do the occasional long journey (500 miles in 1 day).

[Mooly]

7 hours ago, Cyker said:

On a complete tangent, I really wish the Mk4 had the single windscreen wiper the Mk3 has!

I think it was the Audi A2 that was (in)famous for the single wiper actually causing detectable 'rocking' of the car... and you wouldn't like that (lol)